Note: Descriptions are shown in the official language in which they were submitted.
~2S~207
ICIA 1193
TITLE :
Herbicidal 5-pyrimidylcyclohexan-1,3,dione derivatives
This invention relates to organic compounds hav-
ing biological activity and in particular to organic
compounds having herbicidal properties and plant growth
regulating properties, to processes for the preparation
of such compounds, to intenmediates useful in the pre-
paration of such com2ounds and to herbicidal com-
positions and processes utilizing such compounds and to
plant growth regulating compositions and processes
utilizing such compounds.
The use of certain ~yclohexane-1,3-dione deriva-
tives as grass herbicides is ~nown in the art. For ex-
ample, the ~Pesticide Manual~ (C R Worthing E~itor, The
British Crop Prstection Council, 6th Edition 1979) des-
cribes the cyclohexane-1,3-dione derivative ~DUWn
commeroially as alloxydim-sodium (methyl 3-/I-[allyloxy-
imino)bu~l7-4-hydroxy-6,6-dimethyl-2-oxocycloheY-3-ene
carboxylate) and its use as a grass herbicide. lhis
compound is disclosed in Australian Patent No 46~ 655
and its equivalents such as UK Patent No 1 ~61 170 and
VS Patent No 3 950 420.
Mbre recently, at the 1980 British Crop
~,,
~25~2~7
-- 2 --
Protection Conference (~1980 British Crop Protection
Conference - Weeds, Pr~ceedings Vol 1, Research ~eports",
pp 39 to 46, British Crop Protection Council, 1980), a
new cyclohexane-1,3-dione grass herbicide code named
NP 55 (2-~N-ethoxybutrimidoyl)-5-(2-ethylthiopropyl)-3-
hydroxy-2-cyclohexen-1-one) was announced. This com-
pound is disclosed in Australian Patent Application No
A~-Al-35,314/78 and its ecuivalents.
It has now been found that a neh group of cyclo-
hexane-1,3-dione derivatives which have a 5-pyrimidyl
substituent exhibit particularly useful herbicidal
activity.
Accordingly the invention pro~ides a compound of
formula I:
OR 2
/ ~-OR
(X) ~ C ~R3
Yherein:
X, ~hi~h may be the sa~e or different, aIe independently
selected from the group consisting of: halogen; nitro;
c~ano; Cl to C6 alkyl; Cl to C6 al~ l substituted with a
substituent selecte~ from the srou~ ccnsisting of halo-
gen, nitro, hydroxy, Cl to C6 al~ and Cl to C6 alkyl-
thio; C2 to C5 aIkenyl; C2 to C6 alk~-n~l; hydroxy; Cl to
C6 aIkQxy; Cl to C6 al~oxy substit-ùted ~it.;. a substi-
tu2nt selected from halogen and Cl to C6 aI~oxy; C2 to
C al~e~yloxy; C2 to C6 al~nyloY~; C2 t 6
J~ZS1207
oxy; (Cl to C6 alkoxy)carbonyl; Cl to C6 alkylthio; Cl
to C6 alkylsulfinyl; Cl to C6 alkylsulfonyl; sulfamoyl;
N-(Cl to C6 alkyl)sulfamoyl; N,N-di(Cl to C6 aIkyl)~
sulfamoyl; benzyloxy; substituted benzyloxy wherein the
benzene ring is substituted with from one to three sub-
situents selected from the group consisting of hal~gen,
nitro, Cl to C6 alkyl, Cl to C6 alkoxy and Cl to C6
haloalkyl; the group NRSR6 wherein R and R are in-
dependently selected from the group consisting of
hydrogen, Cl to C6 alkyl, C2 to C6 alkanoyl, benzoyl
and benzyl; the groups forD~l and C2 to C6 alkanoyl
and the oxime, imine and Schiff base derivatives thereof;
Rl is selected from the group consisting of: hydrogen;
Cl to C6 alkyl; C2 to C6 aLkenyl; C2 to C6 aIkynyl;
substituted Cl to C6 alkyl Yherein the alkyl group is
substituted with a substituent selected from the group
consisting of Cl to C6 alkoxy, Cl to C6 alkylthio,
phenyl and substituted phenyl ~herein ~he benzene ring
is substituted with from one to three substituents
selected from the group consisting of halogen, nitro,
' 1 C6 alkyl, Cl to C6 haloaIkyl, Cl to C
alkoxy and Cl to C6 aIkylthio; Cl to C6 (alkyl) sulfonyl;
benzenesulfonyl; substituted benzenesulfonyl wherein the
benzene ri~g is substituted with rom one to three sub-
stituents selected from the group consisting of hal~gen,
' Y o~ Cl to C6 aI~yl, Cl to Cs haloalkyl, Cl to
C6 alkoxy and Cl to C6 aIkylthio; an acyl group; and an
inorganic or organic cation;
R2 is selected from the group consisting of: Cl to C6
30 alkyl; C2 to C6 alkenyl; C2 to C6 halo~lkenyl; C2 to C6
alkynyl; C2 to C6 haloalkynyl; substituted Cl to C6
al~yl ~herein the alkyl grou~ is substituted ~ith a sub-
stituent selected frGm the group consisting of halogen,
Cl to C6 al~oxy, Cl to C6 al~ylthio, phenyl and sub-
125~2()7
-- 4 --
stituted phenyl wherein the benzene ring is substituted
with from one to three substituents selected from the
group consisting of halogen, nitro, cyano, Cl to C6
alkyl, Cl to C6 haloalkyl, Cl to C6 alkoxy and Cl to C6
aIkylthio;
R3 is selected from the group consisting of: Cl to C6
alkyl; Cl to C6 fluoroalkyl; C2 to C6 alkenyl; C2 to C6
alkynyl; and phenyl;
R4 is selected from the group consisting of: hydrogen;
halogen; cyano; Cl to C6 aIkyl; and (Cl to C6 alkoxy)-
carbonyl; and
n is an integer selected from 1 and ~.
When in the compound of formula I X is chosen
from the groups formyl and C2 to C6 aIkanoyl and the
oxime, imine and Schiff base derivatives thereof, the
nature of the oxime, inune and Schi~f base derivatives
is not narrowly critical. Although not intending to be
bound by theory, it is believed that in the plant the
(substituted) imine group may be removed to give the
corresponding compound of formula I in which X is ~oxn~l
or C2 to C6 aIkanoyl. Suitable values for the groups
formy~ and C2 to C6 aI~anoyl and the oxime, imîne and
Schiff base derivatives thereof include groups of the
formula -C(R7)=~R8 wherein R7 is chosen from hydrogen
and Cl to C5 aIkyl, and R is chosen fr~m hyarosen, C
to C6 alkyl, phenyl, benzyl, hydroxy, Cl to C6 alkoxy,
phenoxy and benzyloxy.
When in the compound of formula I Rl is chosen
irom acyl the na~ure of the acyl group is not narro~-ly
critical. Although not intending to be bound by theory,
it is believed that when Rl is acyl the acyl group
~ay be removed in the plant by hydrolysis to give the
corresponding campound of formula I in w~ich R is
~25~L207
-- 5 --
hydrogen. Suitable acyl groups include: aIkanoyl, for
example C2 to C6 alkanoyl; aroyl, for example benzoyl
and substituted benzoyl wherein the ~enzene ring is
substituted with from one to three substituents chosen
from the group consisting of halogen, nitro, cyano,
Cl to C6 alkyl, Cl to C6 haloalkyl, Cl to C6 al~oxy
and Cl to C6 alkylthio; and heteroaroyl, for example
2-furoyl, 3-furoyl, 2-thenoyl and 3-thenoyl.
When in the compound of formula I R is chosen
from an inorganic or organic cation the nature of tbe
cation is not narrowly critical. Although not intend-
ing to be bound by theory, it is believed that when
is a cation the cation may be removed in the plant to
give a compound of formula I wherein Rl is hydrogen.
Suitable inorganic cations include the aIkali and
alkaline earth metal ions, heavy metal ions including
the transition metal ions, and the ammonium ion. Suit-
able organic cations include the cation R R R R N
wherein R , R , R and R are independently chosen
from the group consisting of: hydrogen; Cl to C10
alkyl; substituted Cl to C10 alkyl wherein the alkyl
group is substituted ~ith a substituent chosen from the
group consisting of hydroxy~ halogen and Cl to C6
alkoxy; phenyl; benzyl; and the groups substituted
phenyl and substitutea benzyl wherein the benzene ring
is substituted ~ith from one to three substituents
chosen from the sroup consisting of halogen, nitro,
cyano, Cl to C6 aI~yl, Cl to C6 haloalkyl, Cl to C6
alkoxy and Cl to C6 alkylthio.
3C The compouDds of the invention may exist in two
isomeric forms as shswn, below wherein ~ represents
the sroup
~L25~207
-- 6 --
x) n~
C~ ~i ,~N_oR2
\ R ~ \ R
Ia Id
It should be recognized that ffhen Rl is hydrogen,
the compounds of the invention may exist in any one of
four tautomeric forms as shown below.
~ ,9S~ -oR2 ~_oR2
R O R O
IIa IIb
N-OR
IIc IId
12SlZ~7
Suitable X include Cl to C6 aLkyl, Cl to C6
alkoxy, Cl to C6 allcylthio, halogen, Cl to C6 haloaLlcyl,
amino, Cl to C6 aLkylamino and di (Cl to C6 aLkyl) amino.
Suitable R include: hydrogen; Cl to C6 alkyl;
C2 to C6 al)cenyl; C2 to C6 allcynyl; substituted Cl to C6
alkyl wherein the alkyl group is substituted with a ~ub-
stituent selected from the grou~ consisting of Cl to C6
allcoxy, Cl to C6 alkylthio, phenyl and substituted
phenyl wherein the benzene ring is substituted with from
one to three substituents selected from the group con-
sisting of halogen, nitro, cyano, Cl to C6 alkyl, Cl to
C6 haloalkyl, Cl to C6 alkoxy and Cl to C6 aLkylthio;
Cl to C6 laL~cyl)sulfom~l; benzenesulfonyl; substituted
benzenesulfonyl wherein the benzene ring is substituted
~ith from one to three substituents selected from the
group consisting of hal~gen, nitro, cyano, Cl to C6
alkyl, Cl to C6 haloalkyl, Cl to C6 alkoxy and Cl to C6
alkylthio; an acyl grou~; and an inorganic or organic
cation .
Suitable R2 include: Cl to C6 alkyl; C2 to C6
allsenyl; C2 to C6 haloalken~l; C2 to C6 alkynyl; C2 to
C6 haloalkynyl; substituted Cl to C6 aLlcyl wherein the
aL~cyl group is substituted ~ith substituent selected
frc~m the group consisting of halogen, Cl to C6 aLkoxy,
2; Cl to C6 al~cylthio, pheDyl and substituted phenyl
~erein the benzene ring is substituted with from one
to three substituents selecte~ froID the group consisting
of halogen, nitro, q,~ano, Cl to C6 alkyl, Cl to C6
haloal~cyl, Cl to C6 aLl~oxy and Cl to C6 alkylthio.
3C Suitable R3 include: Cl to C6 aLlcyl; Cl to C6
fluoroalkyl; C2 to C6 al3cenyl; C2 to C6 alkynyl; and
p~eny 1 .
Suitable R4 include hydrogen.
Suitable n include the integers 1 and 2.
Preferred ca~?ounds of the invention inc:lude
~25~l20~
those compounds ~f formula I wherein:
X are independently selected from the group consisting
of Cl to C6 alkyl, Cl to C6 alkoxy, Cl to C~ alkylthio,
Cl to C6 alkylsulfinyl, Cl to C6 alkylsulfonyl, halogen,
amino, N-(Cl to C6 alkyl)amino and N,N-di(Cl to C6
aIkyl)anuno;
Rl is selected from the group consisting of: hydrogen;
C2 to C6 alkanoyl; benzoyl and substituted benzoyl
~herein the benzene ring is substituted with from one
to three substituents selected from the group consisting
of halogen, nitro, Cl to C6 alkyl and Cl to C6 alkoxy;
benzenesulfonyl and substituted benzenesulfonyl wherein
the benzene ring is substituted with from one to three
substituents selected from the group consisting of
halogen, nitro, Cl to C6 alkyl and Cl to C~ alkoxy; and
an inorganic or an organic cation selected from ~he
alkali m~tals such as lithium, potassium and sodium,
the aIkaline earth metals such as magnesium, calcium
and barium, the transition metals such as manganese,
cop2er, zinc, iron, nickel, cobalt and silver, the
a3D~iu~ ion and the tri- and tetra-(aIkyl)ammonium
ions ~herein alkyl is selected from Cl to C6 alkyl and
C to C6 hydroxyaIkyl;
R is selected from the group consisting of Cl to C6
25 aI~}l, C2 to C6 alkenyl, C2 to C6 alkynyl, Cl to C6
haloalkyl, C2 to C6 haloalkenyl and C2 to C6 halo-
aL~ynyl;
R is selected from Cl to C6 al~yl;
R- is selected from hydrogen and halogen; and
n is an integer selected fro~ 1 and 2.
~ore preferred cn~pounds of the invention in-
12:51207
_ g _
clude th~se compounds of formula I in which the
pyrimidine ring is linked ~hrough the 5-position to the
cyclohexane ring. That is, compounds of formula IIIo
ORl
,~ ~1i-OR2 III
(X)n ~4
wherein:
X are independently selected frQm the group consisting
of Cl to C6 alkyl, Cl to C6 alkoxy, Cl to C6 al~ylthio,
Cl to C6 alkylsulfinyl, Cl to C6 alkylsulfonyl, halogen,
amino, N-(Cl to C6 alkyl)amino and N,N-di(Cl to C6
alkyl~a~ino;
Rl i5 selected from the group consisting of hydrogen,
C2 to C6 aIkanoyl, benzoyl, the aLkali netals, the
transition metals, the ammonium ion and the tri- and
tetr~-(al~yl)ammonium ions w~erein alkyl is selected
fro~ Cl to C6 aIkyl and Cl to C6 hyGroxyal~yl;
R2 is selected from the sroup consisting of Cl to C3
aI~yl, Cl to C3 haloaLkyl, allyl and haloallyl;
R is ~elected from Cl to C3 alkyl;
R is hydrogen; and
n i5 an integer selected from 1 and 2.
Included among the ~ore preferred coEpo~nds of
1251~17
the invention are those 5-pyrimidyl compounds of formula
III wherein:
X are independently selected from the group consisting
of Cl to C6 alkyl, Cl to C6 alkoxy, Cl to C6 alkylthio
and N,N-di(Cl to C6 aIkyl)amino;
Rl is selected frQm the group consisting of hydr~gen,
C2 to C6 alkanoyl and the alkali metals;
R is selected from the group consisting of Cl to C3
al~yl, allyl and haloallyl;
10 R is selected from Cl to C3 alkyl;
R4 is hydrogen; and
n is the integer 1.
Also included among the re preferred compounds
of the invention are those S-pyrimi~yl compounds which
are substituted in the 2-position of the pyrimidine
ring. m at is, com~ounds of for~ula IIIa
X ~ ~ \ R IIIa
R O
wherein:
X is independ2ntly selecte~ fr the group consisting
of Cl to C6 alkyl, Cl to C6 aIkoxy, Cl to C6 alkylthio,
1251207
-- 11 --
Cl to C6 alkylsulfinyl and N,N-di(Cl to C6 alkyl) amuno;
Rl is selected from the group consisting of hydrogen,
C2 to C6 alkanoyl and the alkali metals;
R is selected from the ~roup consisting of Cl to C3
5 alkyl, allyl and haloallyl;
R3 is selected from Cl to C3 alkyl; and
R4 is hydrogen.
Particularly preferxed values for X include
methyl, methoxy, methylmercapto and N,N-dimethyla-~no.
Particularly preferred values for Rl include
hydrogen, C2 to C6 alkanoyl, sodium and potassiur.
Particularly preferred values for R include
ethyl, n-propyl, allyl and chloroallyl;
Particularly preferred values for R3 include
ethyl and n-propyl.
Examples of compounas embraced by the invention
include:
~ C2~5
1;~51207
,OH
3 ~IC~ C2115
9e~a~
3 ~ ~ C21',5
0~
CH 30 ~ )CH2-C~=C~ 2
OB
3~( 3{~ C2~ 5
3 0
s ~C C2 5 12
o
OCC(CE~3~ 3
~{ ~ C2H5 13
~25~21~7
-- 13 --
O-C--C6H5
CH3~ -C~99 14
Specific examples of the compounds of the in-
vention include those compounds detailed in Tables la
and lb.
~Z51.~7
-- 14 --
ABLE la
Rl 2
~N~OR
~X~n O
Com- . _
. No ( X ) n R R
1 2-C~ 3 El C2~5 n-c3H 7
2 2 -CEI 3S H C2H5 3 7
3 2-CH30 El C2~5 n-c3H 7
4 2-C~3S H C2~5 C2H5
2-CE13S Na ~ 2H5 C2H5
6 2-CE135 ~0) ~ C2~5 C2~5
7 2-C~13 El CH2CH=CEICl n~C3E1 7
8 2-CH30 COC~CH3~ 3 C2~5 n-C3~7
. _ 2--( CE~ 3) 2N ll C2~5 C~35
l;~Sl:~O~
-- 15 --
TABLE lb
ORl
~N-OR
R3
lx)n o
pound ¦( X I D ¦ R ¦ R ¦ R
. . _. _ .
. 10 5-CH 3 11 C2B5 .
~2~2~7
_ 16 --
The compounds of th~ invention may be prepared
by a variety of methods and in a :Eurther aspect the
invention provides methods for the preparation of com-
pounds of formula I.
Conveniently the preparation of the compounds
of the invention can be considered in three or four
parts.
Part A involves the formation of a 5-arylcyclo-
hexan-1,3-dione of formula IX. m is reaction may be
carried out in a two step process b~!:
(i) reacting, preferably in the presence of a base,
an aldehyde derivative of formula V with acetone
(IVa) or an acetone derivatiYe of for~.ula IVb
to form a ketone d~rivative of for~ula VIa or
VIb respectively; and reacting, preferably in the
presence of a base, a ~etone derivative of
formula VIa with a malonic acid ester derivative
of formula VIIa or a ketone derivative of formula
VIb with a ~alonic acid ester of formula VIIb,
to give an interme~ia~e of formula VIIIa or VIIIb
respectively Yhich may be isolated or hydrolysed
directly, preferably in the presence of an acid,
to ~ive a 5-arylcyclohexan-1,3-dione of formula
IX, or reacting, preferably in the presence of a
base, a ketone derivative of forcula Vla with an
alkanoic acid ester of for~.ula ~IIc to give a 5-
arylcyclohex~n-1,3-dione of form~}a IX;
(ii) reacting, preferably in the presence of a base,
an alde~yde deri~ati~e of for~ula V with a
3G malonic acid ester o~ for~ula V~Ib to give an
arylr~thylide~e~zlo-,ate deriYati~e of forr.ula
VIc which is ir. turr. reacted, preferably i~ $he
presence of ~ base, b-ith an acetoacetic acid ester
deri~ative of for~-;la ~ to si~e an intermediate
12X1207
of fsrmula VIIIc which may be isolated or
hydrolysed directly, preferably in the presence
of an acid, to give a 5-arylcyclohexan-1,3-dione
of formula IX; or
(iii) reacting, preferably in ~he prese~ce of a base,
an aldehyde derivative of formula Y with an
acetic acid ester of formula IVc to give a 2-
arylalkenoate derivative of formula Vld which is
in turn reacted, preferably in the presence of
a base, with an acetoacetic acid ester derivativ~e
of formula VII d to give an inter~ediate of
formula VIIIa which may be isolated or hydrolysed
directly, preferably in the presence of an acid,
to gi~re a 5-arvlcyclohexan-1,3-dione of formula
IX.
Part ~ involves the acylation of a compound of
formula IX to give a 2-acyl-5-arylcyclohexan-1,3-dione
of foxmula XIII. This reaction may be carried out by
reacting a 5-arylcyclohexan-1,3-dione of formula IX
with:
(iv) an acid anhydride of formula X in the presence of
either an aIkali metal salt of the corresponding
acid of formula XI or an aIkoxide salt of formula
XII, ~herein ~ is an alkali ~etal ion and R is
2~ Cl to C6 alkyl;
(v) an acid anh~dride of formula X in the presence of
the corresponding acid of for~ula ~IV;
~vi) an acid ha~ide of formula x~r, ~herein hal re-
presents halog~e~ the presence of a Lewis acid
catalyst;
~vii) a ~ixture of an aci~ halide of formula ~V and the
~25120~
- 18 -
correspondins acid o, formula XIV; or
(viii) with an aLkali or alkaline earth metal hydride
followed by reaction with an acid anhydridle of
formula X or an acid halide of formula XV.
Alternatively, this acylation reaction may be
carried out by:
(ix) reacting a 5-arylcyclohexan-1,3-dione of formula
IX with an acid halide of formula XV in the
presence of pyridine to give an intermediate O-
acyl derivative of formula XVI; and
(x) reacting the intermediate of formula XVI with a
Lewis acid catalyst;
(xi) reacting the intermediate of formula XVI with
the acid of formula XIY; or
5 ~xii) reac~ing the intermediate of formula XVI ~ith
imidazole.
Part C involves the for~ation of a compound of
the invention of formula I ~herein Rl is hydrogen, that
is a compound of formula II. This reaction may be
carried out either by reacting a 2-acyl-5~arylcyclo-
hexan-1,3-dione of formula XIII with:
(xiii) an alkoxya~ine derivative of formula XVII; or
~xiv) hydroxylA~ine to give an intermediate oxime
derivative of formula XVIII a~d reacting that
intermediate oxime derivative of formula XVIII
~ith an aLkylating agent of formula XIX ~herein
L ~s a leaving group such as, for example,
chloride, bromide, iodide, sulfate, ~itrate,
methyl sulfate, ethyl sulfate, tetrafluoroborate,
~-~ 1 25 12~7
-- 19 --
hexafluorophosphate, hexafluoroantimonate,
methanesulfonate, flu~rosulfonate, fluoro-
methanesulfonate and trifluoromethanesulfonate.
Part D involves the formation of a compound of
the invention of formula I ~herein Rl is a substituent
other than hydrogen.
Co~pounds of the invention of formula I, wherein
Rl forms an ether, acyl or sulfonyl derivative of a
compound of formula II, may be prepared from ~he corres-
ponding compounds of the invention of formula II by re-
acting with an etherification, acylation or sulfonyla-
tion reagent of formula XX.
Compounds of the invention of formula I wherein
Rl is an inorganic or organic cation may be prepared
fr the compounds of the invention of formula I
wherein Rl is hydrogen, that is, compounds of formula
II, by reacting said compounds of formula II with an
inorganic or organic salt. For example, tbe compounds
of formula I wherein Rl is an aIkali metal ion may be
prepared by reacting the appropriate co~pound of
formula II with the appropriate alkali metal hydroxide
or alko~ylate. The compounds of formula I wherein R
is a transition metal ion or an organic cation ~ay
si~ilarly be prepared by reacting the appropriate com-
pound of formula II with an appropriate transitionmetal salt or organic base. Alternatively the com-
pounds of formula I wherein Rl is a transition ~etal
ion or an organic cation may be prepared by reacting
the appropriate compound of formula I wherein Rl is an
3~ aI}ali ~etal ion with an a~prcpriate transition ~etal
salt or organic salt.
Accordingly, in a further aspect the invention
provides a process for the preparation of a co~p~und of
formula I, as hereinbefore defined, which procYss com-
prises:
~251207
- 20 -
reacting 2-acyl-5-~aryl)cyclohexane-1,3-dione
derivative of formula XIII with an alkoxyamine
derivative of formula XVII to give a cRmpound of
the invention of formula II or reacting the 2-
acyl-5-(aryl)cyclohexane-1,3-dione derivative of
formula XIII with hydroxylamine and aIkylating
the oxime intermediate of for~.ula XVIII with an
alkylating agent of formula XIX, wherein L is a
leaving group, to give a compound of the in-
vention of formula II; and ~ptionally
reacting the compound of the invention of formula
II with a compound of formula XX, wherein L is a
leaving group, to give a compound of the inven-
tion of formula I.
me structures of the compounds described above
are detailed on the following pages wherei~ 0
represents the ~roup
(X~n
1;2 51207
-- 21 --
oRl ~H
~3 ~ //N-OR
R4 R
II
CB 3COCH 3 C~ 3COCH 2 R CH 3C02R
IYa IVb IVc
0-CHO
V
5~-C~--CH-COCH30-C~=CR --COCE33
Vla VIb
S~CH=C ( CO2R) 2~)--CB=C~}--CO2R
Vlc VId
P~ C~; ~C02R) 2CH2 ~C02R? 2
VI I a VI Ib
~25~2V7
R C~ 2 C02R C~ 3CO(~H R Ct:~2R
VIIC VIId
0~ 0~
R4 C02R
co2~
VIIIa VIlIb
RO_C o o
"'2~ ~
VIIIc IX
3 3
(R CO) 2~ C02M ROM
X XI XII
pH
0 ~C~/
~ \R3
R4
2~II
~S~Z07
-- 23 _
R CO2H R COhal
XIV XY
ocoR3
0~
RO
XVI
H2NOR R2L RlL
XYII XIX XX
0~
~N--OH
0~ ~C
~ R3
R O
~VIII
12S~207
-- 24 --
Certain of the intermediate oompounds of
formulae V, YIa, VIb, VIc, VId, VIIIa, VIIIb, VIIIc,
IX, XIII, XVI and XVIII are novel compounds and there-
fore in further embodiments the invention provides
novel compounds of formulae V, VIa, VIb, VIc, VId,
VIIIa, VIIIb, VIIIc, IX, XIII, XVq ~nd XVIII and
processes for the preparation thereof.
For example, none of the pyrimidine-
carboxaldehydes of formula V used in the preparation of
the compounds of the invention of formula I has previously
been described.
Accordingly, in a further aspect the invention
provides a compound of formula V
N~`N
(X) nt~ C~O
wherein X and n are as hereinbefore defined.
A preferred group of coqpounds of the invention
of formula I ~ay be prepared fro~ novel 2-substituted-
pyrim;dine-S-carboxaldehydes. Accordingly in a
fur~her aspect the invention provides pyrimidine-5-
carboxaldehydes of formula Va
~3 va
125~20~
- 25 -
wherein X is as hereinbefore defined.
The compound 2,4,6- trimethoxypyrimidine-5-
carboxaldehyde may be prepared by Yilsmeyer formylation
of 2,4,6-trimethoxypyrimidine using N,N-dimethyl-
formamide and phosphorus oxychloride. ffowever,
Vilsmeyer formulation is only effective with aromatic
compounds which are very reactive towards electrophilic
aromatic substitution and the reaction works in this
instance because of the presence of three strongly
electron donating groups in the pyrimidine ring.
It is not possible to use the Vilsmeyer
formylation reaction to prepare pyri~midine carbox-
aldehydes in which the pyrimidine ring is not activated
by stronyly electron donating groups. For example, it
was necessary to find a new process to prepare the
novel 2-substituted-pyrimidine-5-carboxaldehydes used
in the preparation of a preferrea goup of compounds of
the invention of formula I~ miS new process involves
reacting a 2-(methylene)propanediylidene derivative,
such as for example {2-~dimethylamino)methylene7-
propanediylidene)bis~dimethylammonium perchlorate7,
with an amidine derivative. Accordingly, in a further
aspect the invention provides a process for the pre-
paration of a pyrimidine-5-carboxaldehyde derivatiYe
of formula Va
N
X ~ ~ C~o Va
~hich pro oess comprises reactinq a 2-~methylene~-
propanediylidene deriYati~e of formula XXI wherein R is
selected fro~ Cl to C6 aI~yl ~ith an amidine deri~ati~e
1~5~2(~
-- 26 --
of formula XXII wherein X i~ as hereinbefore defined,
or a salt thereof.
~ CH=~(R)2 N~
(R)2NCH=C X-C-NH2
CH=~(R)2
XXI XXII
In a further embodiment the invention provides
a compound of formula IX
N~N ~
(X)n ~ IX
r~
R4
w~erein X, R4 and n are as hereinbefore defined.
In a still further embodiment the in~ention
provides a com~ound of forDula XIII
0~
(X)n ~ C~ 3 XIII
R4
~rein X, R3, R4 and n al~ as hereinbefore defined.
12S120~
The compounds of formula I are active as herbi-
cides and ~herefore, in a further aspect the invention
provides a process for severely damaging or killing un-
wanted plants which process comprises applying to the
plants, or to the growth medium of the plants, an
effective amount of a cQmpound of formula I as herein-
before defined.
Generally speaking the compounds of formula I
are herbicidally effective against a variety of plants.
However, certain of the compounds of the invention are
selectively active against moncotyledonous plants,
dicotyledonous plants being relatively unaffected by
rates of application of the compounds of the invention
which are severely damaging or lethal to other plant
species.
Accordingly in a further aspect the invention
provides a proc2ss for selectively controlling the growth
of monocotyledonous weeds in dicotyledonous crops which
process comprises applying to the crop, or to the growth
medium of the crop, a compound of formula I in an
amount sufficient to severely damage or kill said weeds
but insufficient to substantially damage said crop.
12S1207
m e compounds of formula I may be applied
directly to the plant (post-emergence application) or
to the soil before the emer~ence of the plant (pre-
emergence application). ~owever, the compounds are,
in general, more effective when applied to the plant
pQS t-emergence.
The compounds of formula I may be used on their
own to inhibit the growth of, severely damage, or kill
plants but are preferably used in the form of a com-
position comprising a cQm~ound of the invention in ad-
mixture with a carrier comprising a solid or liquid
diluent. Therefore, in yet a further aspect the in-
venti~n provides growth inhibiting, plant damaging,
or plant killing compositions comDrising a compound
of formula I as hereinbefore defined and an a~ri-
culturally acceptable carrier therefor.
Certain of the compounds of formula I exhibit
useful plant growth regulating activity. For example,
while cu~ounds of formula I are selectively active
berbicides against wild grasses in crops of cultivated
plants at s e rates of application they exhibit plant
growth regulating effects in said crops.
Plant growth regulating effects m~y be nani-
fested in a number of ways. For example, suppression of
apical dom nance, stimulation of auxiliary bud growth
~2~12(~7
-- 29 --
stimulation of early flowering and seed formation, en-
haDcement of flowering and increase in seed yield, stem
thickening, stem shortening and tillering. Plant growth
regulating effects shown in compounds of the invention
may include, for example, tillering and stem shortening
in cropssuch as wheat and barley.
Accordingly in a still further aspect the in-
vention provides a process for regulating the growth of
a plant which process comprises applying to the plant,
to the seed of the plant, or to the growth medium of the
plant, an effective amount of a compound of formula I,
as hereinbefore defined.
To effect the plant growth regulating process of
the present invention the compounds of formula I may be
applied directly to the plant (post-emergence applica-
tion) or to the seed or soil before the emergence of
the plant (pre-emergence) application.
me cQmpounds of formula I may be used on their
own to regulate the growth of plants but in general are
preferably use2 in the form of a composition comprising
a compound of the invention in a~xture with a carrier
comprising a solid or li~uid diluent. m erefore, in a
still further aspect the invention provides plant
growth regulating compositions comprising a compound of
formula I as bereinbefore defined and an agriculturally
acceptable carrier therefor.
The compositions of the present invention ~y be
in the form of solids, liguids or pastes. The oom-
p~sitions include both dilute o~mpositions which are
ready for i~mediate use and ooncentrated compositions
~hich ~ay require dilution before use. merefore, the
co~centration of the active ingredient in the com-
positions of the present invention will vary depending
on the types cf formulation and whether the coc2osition
35 is ready for use such as, for example, a dust formula- ;
~251ZO~
-- 30 --
tion or an aqueous emulsion or whether the composition
is a concentrate such as, for example, an emulsifiable
concentrate or a wettable powder, which is suitable for
dilution before use~ In general the compositions of
the present invention comprise from 1 ppm to 99% by
weight of active ingredient.
The solid cQmpositions may be in the form of
powders, dusts, pellets, grains, and granules wherein
the active ingredient is muxed with a solid diluent.
Powders and dusts may be prepared by mixing or grinding
the active ingredient with a solid carrier to give a
finely divided co~position. Granules, grains and
pellets may be prepared by bonding the active ingredient
to a solid carrier, for example, ~y coating or im-
pregnating the preformed granular solid carrier with theactive ingredient or by agglomeration techniques.
Examples of solid carriers include: mineral
earths and clays such as, for example, kaolin, bentonite,
kieselguhr, Fuller's earth, Attaclay, diatomaceous earth,
bole, loess, talc, chalk, dclQmite, limestone, lime,
calcium carbo~ate, powdered magnesia, magnesium oxide,
magnesium sulfate, gypsum, calcium sulfate, pyrophyllite,
silicic acid, silicates and silica gels; fertilizers
such as, for example, ammonium sulfate, ammonium
phosphate, a~moniu~ nitrate and urea; natural products
of vegetable ori~in such as, for example, grain meals
and flours, bar~ meals, ~od ~eals, nutshell meals and
cellulQsic pc~ers; and synthetic polymeric materials
such as, for exam2le, ground or powdered plastics and
resins.
Alternatively, the solid compositions may be
in the for~ of dispe-sible or ~ettable du~ts, powders,
granules or grains ~erein the active ingredient and the
solid carrier are co~bined with one or hore surface
active agents ~hic~ act as wettiDg, emulsifying and/or
~25120
- 31 -
dispersing agents to facilitate the dispersion of the
active ingredient in liquid.
Examples of surface active agents include those
of the cationic, anionic and non-ionic type. Cationic
surface active agents include quaternary ammonium com-
pounds, for example, the long chain alkylammonium salts
such as cetyltrimethyla~monium bromide. Anionic surface
active agents include: so~ps or the alkali metal,
aIkaline earth metal and ammonium salts of fatty acids;
the alkali metal, aIkaline earth metal and ammonium
salts of ligninsulfonic acid; the aIkali metal, alkaline
earth metal and am~onium salts of arylsulfonic acids
including the salts of naphthalenesulfonic acids such
as butylnaphthalenesulfonic acid, the di- and tri-
isopropylnaphthalenesulfonic acids, the salts of thecondensation products of sulfonated naphthalene and
~aphthalene derivatives with formaldehyde, the salts of
the condensation products of sulfonated naphthalene and
naph~halene derivatives ~ith phenol and formaldehyde,
and the salts of al~ylarylbenzenesulfonic acids such
as do~ecylbenzenesulfonic acid; the alkali metal,
aIkaline earth metal and a~oni D salts of the long
chain no esters of sulfuric acid or aIkylsulfates
such as laurylsulfate and the m~no esters of sulfuric
acid ~ith fatty alcohol glycol ethers. Nonionic sur-
face active agents include: the condensation products
of et~ylene oxide ~ith fatty alcohols such as oleyl
aloohol and cetyl alcohol; the condensation products of
ethylene oxide with phenols and alkylphenols such as
isoDc~ylphenol, octylphenol and nonylphenol; ~he con-
densation products o~ ethylene oxide with castor oil;
the partial esters deriYed from long chain fatty acids
and hexitol anhydrides, for example sorbitan mono-
laurate, and their co~densation products ~ith ethylene
o~ide; ethylene oxide~pr~pylene oxide block copolymers;
~25~207
lauryl alcohol polyglycol ether acetal; and the
lecithins~
The liquid com?ositions may comprise a solution
or dispersion of the active ingredient in a liquid
carrier optionally containing one or more surface active
agents which act as wetting, emulsifying and~or dis-
persing agents. Examples of liquid carriers include:
water; mineral oil fractions such as, for example,
kerosene, solvent naptha, Detroleum, coal tar oils and
aro~atic petroleum fractions; aliphatic, cycloaliphatic
and aromatic hydrocarbons such as, for example,
paraffin, cyclohexane, toluene, the xylenes, tetra-
hydronaphthalene and alkylated naphthalenes; alcohols
such as, for example, ~ethanol, ethanol, propanol,
isopropanol, butanol, cyclohexanol and propylene glycol;
~etones such as, for example, cyclohexanone and
isophorone; and strongly polar organic solvents such as,
for example, dimethylformamide, dimethylsulfoxide, N-
methylpyrrolidone and sulfolane.
2n A preferred liquid composition comprises an
aque~us suspension, dispersion or emulsion of the active
ingre~ient which is suitable for application by spraying,
atomizing or watering. Such aaueous co~positions are
generally prepared by mixing concentrated c positions
~ith ~ater. Suitable con oe ntrated compositions include
enulsion concentrates, pastes, oil dispersions, aqueous
suspensions and wettable ?owders. The con oe ntrates are
usually required to Yithstand storage for prolonged
periods and after such storage to be capable of dilution
Yith ~ater to form aqueous preparations which remain
homogeneous for a sufficient time to enable them to be
appliec by conventional spray equipment. The con-
oer.trates conveniently contain from 20 to 99~, prefer~
ably 20 to 60%, by ~eight of active ingredient.
Emulsion or emulsifiable concentrates are con-
~251207
veniently prepared by dissolving the active ingredient
in an organic solvent containing one or more surface
active agents. Pastes may be prepared by blending the
finely divided active ingredient with a finely divided
solid carrier, one or more surface active agents and
optionally an oil. Oil dispersions may be prepared by
grinding together the active ingredient, a hydrocarbon
oil, and one or more surface active agents. Aqueous
suspension concentrates may con~eniently be prepared by
ball milling a mixture of the active ingredient, water,
at least one surface active agent and preferably at
least one suspending agent. Suitable suspending agents
include: hydrophilic colloids such as, for exam~le,
poly(N-vinylpyrrolidone), sodium carboxymethylcellulose
and the vegetable gums gum acacia and gum tragacanth;
hydrated colloidal mineral silicates such as, for ex-
ample, montmorillonite, beidellite, nontronite,
hectorite, saponite, sauconite and bentonite; other
cellulose derivatives; and poly(vinyl alcohol). ~ett-
able powder concentrates may conveniently be prepared byblending together the active ingredient, one or more
surface active agents, one or more solid carriers and
optionally one or more suspending agents and grinding
the ~ixture to give a powder having the reauired
particle size.
The aqueous suspensions, dispersions or
emulsions ma~ be prepared from the conoentrated com-
positions by ~ixing the concentrated compositions with
~ater optionally oontaining surface active agents and~or
oils.
It ~hould be noted that the compounds of the
invention of formula I wherein Rl is hydrogen are acidic.
Therefore, the com~ounds of formula I ~ay be formulated
and applied as the salts of organic or inorgaric bases~
In formulatinc an ~loying the compo~Dds of formula I
~25~07
- 3~ _
in the form of their salts either the salts per se, that
is the compounds of formula I wherein Rl is an inorganic
or an organic cation, may be usecl in the formulation or
~he compounds of formula I wherein Rl is hydrogen may be
used in the formulation and the salts generated in situ
by the use of the appropriate organic or inorganic base.
The mode of application of the co~positions of
the invention will depend to a large extent on the type
of composition used and ~he facilities available for its
application. solid compositions may be applied by dust-
ing or any other suitable ~eans for broadcasting or
sDreadin~ the solid. Li~uid co~positions may be
applied by sprayin~, atomizing, watering, introduction
into the irrigation water, or any other suitable means
15 for broadcasting or spreading the liquid.
The rate of application of the compounds of
the invention will depend on a number of factors includ-
ing, for example, the cDmpound chosen for use, the
identity of the plants whose growth is to be inhibited
20 the formulations selected for use and whether the com-
pound is to ke applied for foliage or root uptake. As
a general guide, however, an application rate of from
0.005 to 20 kilograms per hectare is suitable ~hile from
0.01 to'5.0 kilo~rams per hectare may be preferred.
The compositions of the invention ~ay co~prise,
in addition to one or more compounds of the invention,
one or more compounds not of the invention but which
possess biological activity. Por example, as herein-
before indicated the compounds of the invention are in
general substantially more effective against mono-
cotyledonous plants or grass species than against
dicotyledonous plants or br~ad-leaved species. As a
result, in certain applications the herbicial use of the
coGpounds of the inventior. alone ~ay not ke sufficient to
protect a crop. Accordingly in yet a s ill further
~25~2~
embodiment the invention provides a herbicidal com-
position comprising a muxture of at least one herbicidal
compound of formula I as herein~efore defined with at
least one othe~ herbicide.
The other herbicide may ~e any herbicide not
having the formula I. It will generally be a herbicide
having a complementary action. For example, one pre-
ferred class is of mixtures comprising a herbicide active
against broad-leaved weeds. A second preferred class is
of mixtures comprising a contact herbicide.
Example of useful complementary herbicides
include:
A. k~nzo-2,1,3-thiadiazin-4-one-2,2-~ioxides such as
3-isopropylbenzo-2,1,3-thiadizin-4-one-2,2-dioxide
(common name bentazon),
B. hormone her~icides and in particular the phenoxy-
alkanoic acids such as 4-chloro-2-methylphenoxy
acetic acid Icommon name ~CPA), 2-(2,4-dichloro-
phenoxy)propionic acid ~common name dichlorprop),
2,4,5-trichlorophenoxyacetic acid Ico~mon name
2,4,5-T), 4-(4-chloro-2-methylphenox~-)butyric acid
(oommon name MCPB), 2,4-dichlorophenoxyacetic acid
(CQmmOn name 2,4-D), 4-(2,4-dichlorophenoxy)butyric
acid (common name 2,4-DB), 2-(4-chloro-2-methyl-
phenoxy)propionic acid Ico~on Dame mecoprop), and
their derivatives (eg salts, esters, amides and the
like);
C. 3~ l4-halophenoxy)phenyl7~ dial~ylureas such as
3-~4-(4-chlorophenoxy)phenyl7-1,1-dimethylurea
(co~r.on name chloroxuron);
D. dinitrophenols and their der~vatives (e~ acetates)
SUGh as 2-methyl-4,6-dini~rophenol (co~mon name
DNOC), 2-tertiarybutyl-4,6-dinitrophenol Icommon
~25~
- 36 -
name dinoterb), 2-secondarybutyl-4,6-dinitrophenol
(co~mon name dinoseb) and its ester dinoseb acetate;
E. dinitroaniline herbicides such as N',N'-diethyl-
2,6-dinitro-4-trifluoromethyl-m-phenylenediamine
S (common name dinitramine), 2,6-dinitro-N,N-dipropyl-
4-trifluoromethyl~niline (common name trifluralin)
and 4-methylsulfonyl-2,6-dinitro-N,N-dipropylaniline
(common name nitralin);
F. phenylurea herbicides such as N'-(3,4-dichloro-
phe~yl)-N,N-dimethyl~7-ea (common name diruon) and
N,N-dimethyl-N'-~3-(trifluoromethyl)phenyl7urea
(common name fluometuron);
G. phenylcarbamo~loxyphenylcarbamates such as 3-
~(methox~carbonyl~amino7phenyl (3-methylphenyl)-
carbamate (common na~e phenmedipham) and 3~(ethoxy-
oarbonylamino7phenyl phenylcarbamate (common name
desmedipham);
H. 2-phe~ylpyridazin-3-ones su~h as 5-~mjno-4-chloro-2-
phenylpyridazin-3-one (com~lon nam~ pyrazon);
2Q I~ uracil herbicides such as 3-cyclohexyl-5,6~
trimethyleneuracil (ccmmon name lenacil~, 5-~romo-
3-sec-butyl-6-methyluracil (common ~ame bromacil)
and 3-tert-butyl-5-chloro-6-methyluracil (com~on
name terbacil);
J. triazine herbici~es such as 2-c~loro-4-ethyl2mino-6-
(is~propyl~mino)-1,3,5-triazine (co on name
atrazine), 2-chlo~o-4~6-dilethyla7~ino~ 3~s-
triazine ~co~mon na~.e simazine) an~ 2-azido-4-
(iso-propyla~i~o)-6-methylthio 1,3,5-triazine
(commcn n~e azipro2tryne~;
R. l-alkoxy-2-al~yl-3-pheaylurea herbicides such ~s
~L25~0~i7
37 -
3-(3,4-dichlorophenyl)-1-methoxy l-methylurea
(common name linuron~, 3-(4-chlorophenyll-1-
methoxy-l-methylurea (common name monolinuron) and
3-(4-bromo-4-chlorophenyl)-1-methoxy-1-methylurea
(common name chlorobromuron);
L. thiocarbamate herbicides such as S-propyl dipropyl-
thiocarbamate ~common name verolate);
M. 1,2,4-triazin-5-one herbicides such as 4-amino-4,5-
dihydro-3-methyl-6-phenyl-1,2,4-tria~ine-5-one
(common name metamutron) and 4-aminc-6-tert-butyl
4,5-dihydro-3-methylthio-1,3,4-triazin-5-one
(common name metribuzin);
N. benzoic acid herbicides such as 2,3,b-trichloro-
benzoic acid (common name 2,3,6-TBA), 3,6-dichloro-
2~methyoxyben~oic acid ~common name dicamba) and 3-
amino-2,5-dichlorobenzoic acid (common name
chlorambe~n);
o. anilide herbicides such as N-butoxymethyl-~-chloro-
2',6'-~iethylacetanilide ~common name butachlor),
the corresponding N-methoxy compound lcommon name
alachlor), the corresponding N-iso-propyl compound
(common name propachlor) and 3',4'-dichloro-
propionanilide (common name propanil);
P. dihalobenzonitrile herbicides such as Z,6-dichloro-
benzonitrile (common name dichlobenil), 3,5-dibro-
4-hydroxybenzonitrile (common name bro xynil) and
3,5-diiodo-4-hydroxybenzonitrile ~common name
ioxynil).
Q. Hal~alkanoic herbicides such as 2~2-dichloro-
propionic acid (common name dalapon), trichloro-
acetic aci~ ~common name TCA~ ~nd salts thereof;
~L251Z07
- 38 -
R. diphenylether herbicides such as 4-nitrophenyl 2-
nitro-4-trifluoromethylphenyl ether (common name
fluorodifen), methyl 5-(2,4-dichlorophenoxy)-2-
nitrobenzoate (c~mmon name bifenox), 2-nitro-5-(2-
S chloro-4-trifluoromethylphenoxy)benzoic acid and
2-chloro-4-trifluoromethylphenyl 3-ethoxy-4-nitro-
phenyl ether;
S. N-~hetero~rylaminocarbonyl)benzenesulfonamides
such as 2-chloro-N-~(4-methoxy-6-methyl-1,3,5-
triazin-2-yl)aminocarbonyl7ben enesulfonamide
(commonly known as DPX 4189); and
T. miscellaneous herbicides includins N,N-dimethyl-
diphenylacetamide ~common name diphenamid), N-(l-
naphthyl)phthalamic acid (common name naptalam) and
3-amino-1, 2,4-triazole.
Examples of useful contact herbicides include:
U. bipyridylium herbicides such as those in which the
acti~e entity is the l,l'-dimethyl-4,4'-
dipyridylium ion (common name paraquat~ and those
in which the acti~e entity is the 1,1'-ethylene-
2,2'-dipryidylium ion ~common n~ diquat);
V. organoarsenical berbicides such as ~onosodium
~ethanearsonate (common name HS~); and
~. amino acid herbicides such as ~-~phosphonomethyl)-
glycine Icomm~n na~e glyphosate) and its salts
and esters.
~LZ~;12C3'~
-- 39 --
The invention is now illustrated by, but in no
way limited to, the following Examples.
~xample 1
This Example details the preparation of the
mono-substituted pyrimidine-5-carboxaldehydes of
formula V used in the preparation of compounds of the
invention.
(i) {2-/(Dimethylamino)methylene7propanediylidene}
bis~dimethylammonium perchlorate7 was prepared
by for~lation of bromoacetic acid following
the procedure of Alnold (Collect. Czech. Chem.
Comm., 30, 2125 (1965)).
(ii) A suspension of the above perchlorate salt
(14.8 g) and acetamidine hydrochloride (4.0 g)
in methanol (200 ml) was stirred at 40C during
the gradual addition of a solution of sodium
(1.0 g) in methanol (50 ml). After 3 hours the
solution was neutralized with acetic acid and
evaporated under reduced pressure. The residue
was diluted with water (50 ml) and extracted
~ith chloroform (2 x 100 ml). The chlorof~rm
extracts were dried and evaporated to give 2-
methylpyrimidine-5-carboxaldehyde (2.5 g, 49%).
Theproduct was characterized by proton nuclear
magnetic resonance s2ectroscopy and the spectrum
i5 recorded in Table 2 below.
The mono-substituted pyrimidine-5-carboxaldehydes
of formula V listed in Table 2 below were prepared from
{2-~dimethylamino)methyle~e7propanediylidene bis-
~dL~ethylam~onium perchlorate7 and the appropriate
~midine hydrochloride follovin~ the proced-mre described
~bo~e for the preparation of 2-æ thylpyrimudine-5-
~2S~
- 40 -
carboxaldehyde. The products were characterized by
proton nuclear magnetic resonance spPctroscopy and the
spectroscopic data are recorded i~ Table 2 below.
TABLE 2
X~CHO
X Position of ~ Proton Chemucal Shift ~ in
CH0 Group ppm (CDC13)
2-CH3 5_ 2.90 (3H,s); 9.02 (2H,s);
1~.06 tl~,s).
2-CH3S5_ 2.60 (3H,s); 8.87 (2H,s);
9.96 (lH,s).
2-CH3O5_ 4.10 (3~,5); 8.92 (2~,s);
. 9.95 (l~,s).
Example 2
2~ (Ethoxyimino)butyl7-3-hydroxy-5-t2-methyl-5-
~rimidyl)cyclohex-2-en-1-one (1)
(i) A ~Dlution of 2-methylpyrimidine-5-carboxaldehyde
~4 g) in acetone (50 ml) and ~ater (30 ml) was
la treated with a solution of agueous sodium
hydroxide ~2~, 5 ml) ~qth stirring at 20C. ~he
solution was allowed to stand at room temperature
oYernight and then concentrated under reduced
pressure and neutralized ~it~ dilute hydrochloric
acid. The mixture was extracted dried over
anhydrous magnesium sulphate and evaporated under
reduced pressure to give l-f 5-(2-~e~hyl-
pyri~idyl)~but-l-erl-3-one (2 3 g, ~3~) as a pale
broYn oil.
~l25~26~7
- 41 -
(ii) Diethylmalonate (3.9 ml) was added to a stirred
solution of ~odium metal (0.56 y) in absolute
ethansl ~40 ml) and the solution was heated
under reflux. 1-~5-(2-Methylpyrimidyl7but-1-
en-3-one ~2.3 g~ was added and the mixture was
heated under reflux for a period of 2 hours.
An aqueous solution of sodium hydroxide (2.0 g,
30 ml water) was added and the solution was re-
fluxed for a fur~her 5 hours. The hot solution
was acidified to pH 4 with concentrated hydro-
chloric acid (caxbon dioxide evolution) and
then made alkaline ~y the addition of sodium
bicarbonate. Evaporation ~f the s~lution to
dryness gave the sodium salt of 3-hydroxy-5-
~methylpyrLmidylL7cyclohex-2-Pn-l-one (2.3 g,
72~) as a pale brown solid, mp >200C.
(iii) The sodium salt of 3-hydroxy-5-~5-(2-methyl-
pyrimidylL7cyclohex-2-en-1-one (2 . O g) was
dissolved in dimethylformamide (10 ml) with
stirring at 90C. Butyric anhydride (1.4 ml)
was added to the solution and the heatin~ was
continued at 110C for 1 hour. The dLmethyl-
formamude was evaporated under reduced pressure
and the residue was dissolved in ~ater (20 ~1)
and chloroform (40 ml). The chloroform layer
was separated, dried over anhydrous magnesium
sulphate and evaporated to give an oil which was
purified bX column chromatography over silica
gel (eluant chloroform) to give 2-butyry1-3-
hydroxy-5~ (2-methylpyrimudyl)7cyclohex-2-en-
l-vne (800 mg; 30%~ as an oil.
liv~ Ethoxyamine hydrochloride (240 mg, 2.5 mmol~
a~d then sodiu~ hydroxide ~100 mg) in water (1
ml) were addec to a solution o~ 2-butyry1-3-
hydroxy-5-~5-~2-methylpyrimidyl)/cyclohex-2~n-
12~ 7
- 42 -
l-one (600 mg; 2.2 mmol) in ethanol (50 ml)
with stirring at room temperature. After 20
hours the ethanol was removed ~y evap~ration
under reduced pressur~. The residue was
S dissolved in chloroform, washed with wat~r and
then the organic layer was separated~ dried
over anhydrous magnesium sulphate and evaporated
to give 2-~I-(ethoxyimino~butyl7-3-hydroxy-5-
/5-(2-methylpyrimidyl~7cyclohex-2-en-l-one
(600 mg; B7~) a~ a pale brown oil.
The product and each of the intermediates were
characterized by proton nuclear resonance spectroscopy
and the spectra for the interme~iates and final product
are recorded in Examples 11, 12 and 13, Tables 3, 4 and
5.
Example 3
2~ (Ethoxyimino) butyl7-3-hydroxy-5-/5- (2-methylthio-
pyrimidyl~cyclohex-2-en-l-one (2) and 2-~1-(ethoxy-
imino)butyl7-3-hydroxy 5-~5-(2-methoxypyrimidyl) 7-
c~clohex-2-en-l-one (3) were prepared from the
appro~riate pyrLmidine-5-carboxaldehyde following
essentially the same procedure as that describe~ in
~xample 2 parts (i) to (iv).
Each of the products and intermediates were
characterizea by proton nuclear m~gnetic resonance
spectroscopy and spectroscopic data are recorded in
Examples 11, 12 and 13, Tables 3, 4 and 5.
2-~- (Ethox~L~ino)propyl7-3-hydroxy-5-~5-(2-methyl-
tniopyrimid~lL7cyclohex-2-en-l-one ~4) was prepared
following esse3tially the same procedure as that des-
cribed in Exam~le 2 parts ~i) to (i~) exc~pt for ~he
1~5~207
_ 43 -
use of DrOpiOniC anhydride in part (iii) instead of
butyric anhydride. The product and intermediate were
characterized by proton magnetic resonance spectroscopy
and the spectra are recorded in Examples 12 and 1
Tables 4 and S.
Example 5
2-~I- (Ethoxyimino)propyl7-3-hydroxy-5-~5-(2-methyl~
thiopyrimidyl)7cyclohex-2-en-l-o~e sodium salt (5)
~o a solution of 2~ ethoxyimino)propyl7-3-
10 hydroxy-5-~5-(2-methylthiopyrimidylL7cyclohex-2-en-1-
one (180 mg) in methanol (30 ml) was added a solution
of sodium hydroxide in methanol (1.1 ml of a solution
o~ 1~0 g in 50 ml methanol). The solution was
evaporated under reduced pressure to give the sodium
15 salt (5) of 2-~1-(ethoxyimino)propyl)-3-hydroxy-5-
~5-~2-methylthiopyrimidylL7cyclohex-2-en-1-one as a
pale brown solid, mp ~200C.
Example 6
2-~l-(Ethoxyimino)propyl7-3-hydroxy-5-~5-(2-meth
sulfinylpyrLmidyl)7cyclohex-2-en-1-one (6)
A solution of 2-~ ethoxyimino)propyl7-3-
hydroxy-5-~5-~2-methylthiopyrimidyl)7cyclohex-2-en-1-
one (600 mg) in dichloromethane (10 ml) was treated
at 5C with a solution of 3-chloroperbenzoic acid ',
25 (400 mg) in dichlor~methane (30 ml). The solution
S allowed to warm to room temperature and to stand
for 24 hours. The solvent was removed under reduced
pressure and the residue ~as purified by column
chroma.ography over silica gel (eluant chloroform) to
30 ~ive 2-~1-(ethoxyLmino)pro2yl7-3-hydroxy-5-~5-(2-
~ethylsulfin~lpyrLmidyl)7cyclohex-2-en-lone (6)
(300 mg, 46%) as a nearly colourless solid. The
1~51~1~7
- 44 -
product was characterized by proton magnetic
resonance spectroscopy and the spectru~ is recorded in
Example 13, Table 5.
Example 7
5 2-/~-(3-Chloroallyloxy)butyl7-3-hydroxy-5-~5-(2-
methylpyrimidylL/cyclohex-2-en-1-one (7) was prepared
from 2-butyryl-3-hydroxy-5-~5-(2-methylpyrimidyl) 7-
cyclohex-2-en-1-one and 3-chloroallyloxyamine following
essentially the same procedure as that described in Ex-
ample 2, part (iv1. The product was characterized
by proton magnetic resonance spectroscopy and the
spectrum is recorded in Example 13, Table S.
Example 8
3-Trimethylacetyloxy-2-~I-(ethoxyimino)butyl7-5-
15 ~5-(2-methoxypyrimidyl)7cyclohex-2-en-1-one (8)
Trimethylacetylchloride ~0.10 g) was added
~ith stirring to a solution of 2-~1-(ethoxyLmino)-
butyl7-3-hydroxy-5-~5-(2-methoxypyrimidyl)7cyclohex
2-en-1-one (3) (0.15 g) and 3-picoline (0.10 g) in
dichloromethane (10 ml) at room temperature. After 2
hours at room temperature the solution was washed ~ith
dilute hydrochloric acid ~lM, 10 ml), separated,
dried o~er anhydrous magnesium sulphate and evaporated
under reduced pressure to give 3-trimethylacetyloxy-2-
25 ~1-(ethoxyimino)butyl7-5-~5-(2-methoxypyrimidyl) 7
cyclohex-2-en-1-one (~) as a colourless oil (15G mg).
The productwas characterized by pro~on magnetic
resonance spectrosco2y and the spectroscopic data is
recorded in Table 5, Example 13.
~2SlZO~
- 45 -
Example 9
2-~I- (Ethoxyimino~propyl7-3-hydro~y-5-/5-(2-dimeth
aminopyrimidyl~7cyclohex-2-en-l-one 1 9) was isolated
-
by chromatography during the purificatîon of 2-~I-
(ethoxyimino)propyl7-3-hydroxy-5-/5-~2-methylthio-
pyrimidyl)7cyclohex-2-en-1-one (4) Presumably the
dimethylamino group was introduced during the acylation
step (Example 2 part (iii)) which is carried out in
dimethylformamide at 110C.
The campound was characterized by prc>ton nuclear
magnetic resonance s2ectroscopy and the spectrum is
recoxded in Example 13, Table 5.
xample 10
2-~I- [Ethoxy~mino)propyl7-3-hydroxy-5-~2-(5-methyl-
~yrimidyl)7cyclohex-2-e~ one (10~
(i) 2-Hydroxymethyl-5-methylpyrimidine was prepared
by the reaction of 3-ethoxy-2-methyl acrolein
and hydroxyacet~ridine hydrochloride following
a similar procedure to that described by Kim
and McRee ~J. Ors. Chem., 35, 455 (1970)).
Proton magnetic resonance spectrum (CDC13; ~ in
ppm): 2.32 (3~,s); 3.6 llH,bs); 4.80 l2B,s);
8.54 ~2~,s~.
(ii) 5-MethylpyrLmidine-2-car~oxaldehyde was prepared
from ~-hydroxymethyl-5-methylpyrLmidine by
oxidation ~ith eYcess manganese dioxide in boil-
ing chloroform. Ihe product was obtained as
colourless crystals an~ ~as characterized ~y
proton nuclear ha~ne.ic resonance spectroscopy.
Proton nuclear ~2~netic reconance spectrum
ICDC13; ~ in ppm~: 2.44 ~3~,s); 8.80 12H,s);
10.06 (lH,s).
125~Z07
- 46
(iii) 2~ (Ethoxyimino)propyl7 3 hydroxy-5-~2-
(5-methylpyrimidylL7~yclQhex-2-en-1-one (18)
was prepared from 5~methylpyrimidine-2-
carboxaldehyde followiny essentially the same
procedure as that described in Example 2
partsi (i) to ~iv). ~ach intermediate and the
product was characterized by proton magnetic
resonance spectroscopy and these are recorded
in Examples 11, 12 and 13, Table 3, 4 and 5.
Exam~le 11
The l-~mon~-substituted pyrimidyl)but-l-en-3-
ones of formula VIa used in the preparation of the
compounds of formula I ~ere characterized by their
proton nuclear magnetic resonance (pmr) spectra. For
convenience the pmI data are recorded in Table 3 below.
TABLE 3
(X)n ~ C~=CHCOC~3 VIa
(X) Position of Proton Chemical Shift
n enone group ~ in ppm (CDC13~
2-CB3 5 2.39(3~,s), 2.75(3~,s); 7.08
(2~,dofa~; B.74~2~,s).
2-CH3S 5 2.35(3H,s1; 2.55(3~,s); 7.04
(2~,dofd); 8.61(2H,s).
2-C~30 5 ! 2 38(3~ s); 4 04(3~ s); 7 04
, (2~,dofd)~ 8.65(2~,s).
5-C~3 2 , 2.35(~,s); 2.43(3H,s); 7.2-
. i 7.8~2~,D~; 8.57(2~,s).
~25:12~)~
- 47 -
~xample12
The 2-acy1-5-(mono-substituted pyrimidyl)cyclo-
hexan 1,3-diones of formula XIII used in the preparation
of compounds of formula I were chara~terized by their
proton nuclear magnetic resonance spectra. For con-
venience the pmr data are recorded in Tatle 4 below.
The majority of ~he compounds were obtained as oils or
low-melting point solids and were generally colourless
or ~ale brown.
~ABLE 4
(X ~ R3
. Po6ition of Prot~n Chemical Shift
Substituents Pyr~dine ~ in ppm ~ 13)
~X~n = 2 C~3 1.00(3B,t); 1.7~2B,m);
R = n-C3H7 2.71(3E,s); 2.6-3.6(7H,m);
8.52~2~,s); 18.27(L~,s)
(X~ = 2-C~3S 5 0.99(3~,t~; 1.7(2H,m);
R = n-C3~7 2.55(3H,s); 2.5-3.6(7~,m);
8.39(2~,s); 18.27llH,s).
~X) = 2-C~3O 5 0.99(3H,t); 1.7(2E,m);
R = n-C3H7 2.6-3.6(~B,~); 3.98(3~,s);
8.39(2B,s); 18.2(1ff,s).
~X)n = 5 C~3 2 1.13(3E,t); 2.30(3E,s);
, R = C2B5 2.4-3.9(7~,~); 8.50(2H,s);
18.16(1~,s).
(X)" = 2-C~3S 5 1.16(3H,~); 2.53(3~,s);
R = C2B5 2 5-3 S~7E ~); 8.40~2~,s);
~L25~ZO~
- 48 -
The maiority of the ~ono-substituted pyrimudyl
compounds of the invention ~ere obtained as cslourless
or light brown oils or low-~elting point solids and
were characterized by and can be identified by their
nuclear magnetic resonance spectra. For convenience
proton nuclear magnetic resonance spectroscopic Ipmr)
data are recorded in Table S below.
TABLE 5
. _ _ .
Canpound Proton Chemi ca 1 Shi f t
No~ in pprn (CDC13)
1 0.99(3H~t~; 1.34(3Hrt); 1.7(2H,m); 2.70
(3H,s); 2.6-3.6(7H,m); 4.11(2H,q); 8.50
(2B,s); 15.6(1~,bs).
2 O.9B(3~,t); 1.33(3~,t); 1.7~2H,m); 2.56
~3H,s); 2.5-3~7(7H,m); ~.12(2H,q); 8.44
(2H,s); 15.5~1~,bs).
3 0.99(3~,t); 1.33(3H~t); 1.6(2H,m); 2.5-3.6
~7H,m); 4.oo(3a~s); ~.12(2H,q); 8.43(2~,s);
15.5(lH,~s).
4 1.16(3~,t); 1.34(3E,t); 2.56(3H,s); 2.5-3.6
(7H,m); ~.13(2~,q); 8.44(2B,s); 15.011B,bs).
Not recor~ed
Ç 1.16(3~,t); 1.33(3~,t); 2.5-3.7(7H,m);
2.98(3B,s); 4.12~Z~,g~; 8.77(2H,s); 15.0
(l~,bs).
7 0.98(3~,t); 1.6(2~,m); 2.72(3B,s); 2.6-
3.6(7H,m3; 4.67(2~,dofd); 5.8-6.412H,~);
8.48(2H,s); l5 0~1~,bs).
~25~20~
_ 49 -
TABLE 5 - eontinued
.__ _ ,...... _. ... .
Proton Chemucal Shift
Compound ~ in ppm (CDC13)
__._ _ __. _
8 0.98(3H,t?; 1.2519H,s~; 1.34(3H,t); 1.6
(2H,m); 2.5-3.6(7~,m); 4.00(3H,s); 4.12
(2~,q); 8.45(2H,s).
9 1.15(3H,t) 1.34(3H,t) 2.5-3.6(7H,m); 3.17
~6H,s); 4.12(2~,q); B.25(2~,s); 15.0(1H,bs)
1.12(3~,t); 1.33(3~,t); 2.33(3~,s); 2.5-
3.8(7H,m); 4.12(2H,q~; 8.47~2~,s); 14.8
_ _ (lH,bs).
ExamRle 14
This DOn-limiting Example illustrates the pre-
paration of formulations of the compounds of the in-
vention.
a) Emulsifiable Concentrate
Compound No 1 was dissol~ed in toluene containing7% v/v ~Teric~ ~13 and 3~ v/v ~Remmat~ SC15B to
give an emulsifiable concentrate ~hich may be di-
luted with ~ater ~o the reguired conoentration to
give an aqueous e~ul~ion which ~ay be applied by
spraying.
S'Teric~ is a ~rade ~ar~ and ~Teric~ N13, is aproduct of ethoxylation of nonylphenol; ~Kemmat~ is
a Trade ~ark and ~Kemma~ SC15B is a formulation
of calcium dodecyIbenzenesulfonate.)
~251;~0~
- 50 -
b) ~4ueous Suspension
Ccmpound No 1 ~5 parts by ~eight) and ~Dyapol" PT
(1 part by weight) ~ere adde~ to an aqueous solution
(94 parts by weight) of ~Teric~ N8 and the mixture
~as ball milled to produce a stable aqueous sus~
pension which may be diluted with ~ater to the re-
quired concentration to give an a~ueous suspension
~hich may be applied by spraying. ("Dyapol" is a
Trade Mark and ~Dyapol~ PT is an anionic suspending
agenti VTeric~ n8 is a product of ethoxylation of
nonylphenol.)
c) Emulsifiable Concentrate
Compound Nol(10 parts by weight~, ~Teric" N13
(5 parts by weight) and ~Remmat~ SC15B (5 parts by
weight) were dissolved in ~Solvesso~ 150 (80 par~s
by weight) to ~ive an emulsifiable concentrate
~hich ~ay be diluted with water to the required con-
centration to give an aqueous emulsion which may be
applied by spraying. (~Solvesso~ is a Trade Mark
and ~Sslvesso~ 150 is a high boiling point aromatic
petroleum fraction . )
d~ Di~persible Powder
Compound No 1 (10 parts by ~eight), nMatexil~ DA/AC
(3 parts by weight), 'Aerosol~ OT/B (1 part by
~eight) and china clay 298 (86 parts by weight~
~ere blended and the~ Qilled to give a powder com-
position having a particle size below 50 microns.
(~ffa~exil~ is a Trade ~ark and 'Matexil" DA/AC is
the disodium salt of a naphthalenesulfonic acid~
forDaldehyde concensate; Aerosol- is a Traae ~ark
and ~A2rosol~ OT/B is a f~nmulation of the dioctyl
ester of sodium sulfosucci~ic acid.)
~L2S~ 7
-- ;l
e) ~i2~h Strength ~oncentrate
Compound No 1 (99 parts by weight), ~ilica aerogel
~O.5 parts by weight) and synthetic ~morphous
silica (0.5 parts by ~eight) were blended and
ground in a hammer-mill to produce a powder h~ving
a particle size less than 200 microns.
f) Dustiny ~owder
Compound No 1 llO parts by weight1, attapulgite
(10 parts by weight) and pyrophyllite (8~ part~i by
lQ weight) were ~horoughly blended and then grvund in
a hammer-mill to produce a powder of particle size
less than 200 microns.
Emulsifiable con oe ntrates and/or suspensions of
tbe com?ounds of the invention were prepared essentially
as described in part a), b) or c) above and then
dilubed with water, optionally containing surface active
agent and/or oil, to give aqueous coTpositions of the
required concentration ~hich were used, as described in
E~amples 15 and 16, in ~he evaluation of the pre-
ecærgence and post-~mergence herbicidal ac~ivity of
the compo~n~s.
E~ample 15
The pre-emergent herbicidal actiYity of the com-
pounds of the invention formulated as described in
Exanple 14 ~as assessed by he follo~ ~ g procedure:
The seeds of the test species were ~own in ro~s
2 c~ deep in soil contained in seed boxes. me wno-
co~ledonous plants and the dicotyledc~nous pla~ts ~ere
so~n in separate boxes and af ter ~ ing the t~o bo: ces
30 ~ere ~;prayed ~ith t~e required qua~ y of a composition
of t~e irvention . Two dupl i cate seed bo~es were pre-
~25~L2~37
- 52 -
pared in the same manner but ~ere not ~prayed with a
composition of the invention and ~ere used for com~
parison purposes. All the boxes were placed in a glass-
house, lightly ~atered with an overhead spray to
iDitiate germination and then sub-irrigated as required
for optimum plant growth. After three weeks ~he boxes
were removed frQm the glass house and the effect of the
treatment was visually assessed. The results are pre-
sented in Table 6 where the damage to plants is rated
10 on a scale of form O to 5 where O represents ~rom o to
10% damage, 1 represents from 11 t~ 30% damage, 2
represents from 31 to 60~ damage, 3 represen~s from 61
to 80~ damage, 4 represents from 81 to 99% damage and 5
represents 100X kill. A dash (-) means that no experi-
5 ment was carried out.The names of the test plants are as follows:
~h Wheat
Ot ~ild Oats
Rg Ryegrass
3m Japanese millet
P Peas
Ip Ipomea
Ms ~ustard
Sf Sunflower
~;~5~2~
-- 53 --
T~I~: 6
PRE-EMEROE:NOE EIERBICIDAL I~TI~ITY
. _ .
pOumnd ~PLI ~TION l~:ST PI~NT
No Rate ~kg/ha) ~ . . _ _. _
Wh Ot Rg Jm P Ip Ms S f
_ ..~ ___ __
1 1.0 4 ~ 5 5 O O O
3 1.0 4 5 ~ 5 0 0 0 0
3 0.25 2 3 4 3 ~ 0 0 0
4 1.0 3 5 5 5 0 0 0 0
1.0 5 5 5 5 û O O 0
Example 1 ~
The post-enPrgent herbicidal activity of the
cc~pounds of the inverltion :Eormulated as described in
5 Ex2~le 14 ~as assessed b~ the foll~iing procedure.
The seeds of the tes t species ~ere sown in
rs~ws 2 cm deep in soil cc~Tltained in seed boxes. The
~onocotyleds:lnous plants and the dico~ledonous plants
~ere sa~ eparate seed boxes in d~ ate. The
10 four seed boxes ~ere placed in ~ glass house, lightly
7ratered with an overhea~l spray to initia~e germination
a~d then sub-irri~ated as reguired for optimum plant
growth. After the plar~ts had gr~ bD a heiqht of
~bout 10 to 12 . 5 c~m one }:~ox of each of the mono-
15 ootyledonous plants and diootyledonous plants wasremoved fron~ the glass house aDd sprayed ~ith the re-
~ired qua~tity of a cc~posi~ion of ~h~ invention.
~25~20'7
- 54 -
After spraying the boxes ~erc returned to the glass
house for a further 3 weeks and the effect of treat-
ment was visually as~essed by ca~parison with the un-
treated contols. ~he results are presented in Table
7 where the damage to plants is rated on a scale of
from 0 to 5 where 0 represents from 0 to 10% damage,
1 represents from 11 to 30% damage, 2 represents from .
31 to 60% da~age, 3 represents from 61 to 80% damage,
4 represents frQm 81 to 99% damage and 5 represents
100~ kill~ A dash (-~ means that no experiment ~as
carried out.
The names of the test plants are as follows:
Wh ~heat
Ot ~ild Oats
Rg Ryegr cs
3m Japanese millet
P Peas
Ip Ipa~ea
~s Mustard
Sf Sunfl~er
3l ;2 5 1i~ldV7
-- ~5 --
TABLE 7
POST-EMERGENOE HEP~BICIDAL ACTIVITY
TES T PLANT
Com-- APPLI CATION
pound Rate (kg~ha~ __ ___ _
~h OtRg Jm P Ipl~s S f
___ ~ _
1 1.0 5 5 5 5 0 0 0 0
1 0.25 S 5 ~ 5 0 0 0 0
1 0.06 3 5 5 5 0 0 0 0
2 1.0 0 5 5 4 0 0 0 0
2 0.25 0 ~ 4 3 0 ~ 0 0
3 1.0 5 5 5 5 0 0 0 0
3 0.25 4 5 5 S 0 0 0 0
3 0.06 2 5 4 4 0 0 0 0
4 1.0 5 5 5 5 0 0 0 0
4 0.25 5 5 5 5 0 0 0 0
4 0.06 3 4 5 5 0 0 0 0
1.0 5 5 5 5 0 0 0 0
0.25 5 ~ 5 5 O O O û
0.06 3 3 ~ 4 0 0 0 0
1~ 1.0 3 5 5 5 0 0 0 0
~) 0.25 1 3 _ 3 O 0 0 O
125~ 37
_ 56 -
Example 17
me c~mpounds were formulated for test by
mixing an appr~priate amount with 5 ml of an emulsion
prepared by diluting 160 ml of a solution containing
21.9 g per litre of "Span~ 80 and 78.2 g per litre of
~Tween~ 20 in methylcyclohexanone to 500 ml with water.
"Span~ 80 is a Trade Mark for a surface-active agent
comprising sorbitan monolaurate. ~ween" 20 is a ~rade
Mark for a surface-active agent comprising a condensate
of ~orbitan monolaurate with 20 molar proportions of
ethylene oxide. Each 5 nl emulsion containing a test
compound was then diluted to 40 ml with water and
~prayed on to yo~ng pot plants (post-emergence test)
of the species named in Table 8 below. Damage to test
plants was assessed after 14 days on a scale of 0 to
5 where 0 is 0 to 2~% damage and 5 is is complete ~ill.
In a test for pre-emergence herbicidal activity, seeds
of the test plants were s~wn in a shallow slit formed
in the surface of soil in fibre trays. ffle surface was
then levelled and sprayed, and fresh 50il then spread
thinly over the sprayed surface. Assessment of herbi-
cidal damage was carried out after 21 days using the
same scale of 0 to 5 as the post-emergence test. In
both cases the degree of herbicid~l damage ~as assessed
by co~parison with untrea~ed control plants. The re-
sults are given in Table 8 below. A dash (-~ means
that no experiment was carried out.
The names of tbe test plants ~ere as follows:
Sb Sugar beet
Rp Rape
Ct Cot~on
Sy Soy bean
~z ~ ze
~w ~inter ~he~t
~L253 ~
- 57 -
Rc Rice
Sn Senecio vulgaris
Ip Ipomea plLrpurea
Am Amaranthus retroflexus
Pi Polygonum aviculare
Ca Chenopodium al~um
Ga Galium aparine
Xa Xanthium pensylvanicum
Ab Abuti 70n theophrasti
Co Cassia obtusîfolia
A~ Avena fatua
Dg Digitaria sanguinalis
Al Alopecurus myosuroides
St Setaria viridis
~c Echinochloa crus-~alli
Sh Sorghum hale~ense
Ag ~gropyron repens
Cn Cyperus rotundas
125~207
-- 58
ABLE 8 - PAR~ A
_ ._ _ ___ _
Cn- APPLI CATIONTEST PLANT
pound ~4e'cht>d Rate _ _ __ I_
llo (~g~ha) Sb ~P Ct Sy Mz Ww Rc Sn Ip Am
1 POST O.1_ _ _ _ 5 4 4 _ _ _ _
1 POST 0. 0 2 _ _ _ _ 3 3 3 _ _ _
2 PE~: Q . 4 _ _ _ _ _ tl _ _ _ _ _ _
2 POST 0.05 _ _ _ _ 1 O O _ _ _ _ _
3 }'OS T 0 . 0 5 _ _ _ _ 3 O 4 _ _ _ _ _
3 POST Q . 0 2 _ _ _ _ 2 O O _ _ _ _ _
~2S121D7
_ 59 --
TABLE 8 - PART B
-- _ _ . .
Ca~- APPLICATION TEST PLA~r
pound Method R~te
No (kg/ha) Ga Xa Ab Co ~v Dg Al St Ec Sh Ag Cn
_ ...... _ __ _ _ _
~ POST 0 . 1 _ _ _ _ 4 4 5 5 4 ~ ~
1 POST 0.02 _ _ _ _ 4 4 4 4 3 4 O _
PRE 0.~ _ _ _ _ 3 _ 5 _ _ _ _ _
2 POST 0 . 0 5 _ _ _ _ 4 3 4 4 4 3 O
3 POST 0 . OS _ _ _ _ 4 4 4 4 5 4 4
3 POST 0.,02 _ _ _ _ 3 3 4 4 4 3 O _
