Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
0
RAN 6102/24
The present invention is concerned with propionic
acid esters. The propionic acid esters provided by the
present invention are compounds of the general formula
R5
R ~ 0 ~ ~ ~ COOCH20 ~
wherein Rl represents a hydrogen atom, an alkyl
group containing 1-6 carbon atoms or a phenyl
group, R2 represents an alkyl group containing
1-6 carbon atoms, an alkenyl group containing
2-6 carbon atoms, an alkynyl group containing
2-6 carbon atoms or a phenyl group or Rl and
R2 together with the carbon atom to which they
are attached ~orm a cycloalkane ring containing
- 15 4-10 carbon atoms which, i, desired, can be mono-,
di- or tri-substituted with alkyl containing
1-3 carbon atoms, R3 represents a halogen atom
Pa/31.10.80
0
- 2 -
or a trifluoromethyl or nitro group and R4 and
R each represent a hydrogen or halogen atom.
The invention is also concerned with a process
for the manufacture of the compounds of formula I,
S (pre-emergence and post-emergence) herbicidal compositions
which contain at least one compound of formula I as the
active substance and the use of said compounds or said
herbicidal compositions.
The process provided by the present invention
for the manufacture of tne compounds formula I herein-
before comprises
(a) reacting a salt of an acid of the general formula
R3 ~ o ~ O ~ COOH II
wherein R3, R4 and RS have the significance
given earlier,
with a compound of the general formula
0
RlR2CNOC~2X III
wherein Rl and R2 have the significance given
earlier and X represents a leaving group,
or
(b) reacting a compound of the general formula
/R1 IV
Z~/coocH2oN~
wherein Z represents a leaving group and
and R have the significance given earlier,
with a compound of the general formula
R5
R~O~OH V
: R4
0
-- 4 --
wherein R3,R4 and RS have the
significance given earlier,
or with an alkali metal salt thereof, if necessary in the
presence of a base,
or
S (c) reacting a compound of the general formula
R5
R ~ O ~ COOCH ~ R6 VI
wherein R6 represents a lower alkyl, an aryl
heteroaryl group and R3, R4 and R5 have
the significance given earlier,
with an oxime of the general formula
RlR2cNoH VII
wherein Rl and R2 have the significance
given earlier,
or with an alkali metal salt thereof in the presence
lS of a base.
,
O
- s -
The alkyl groups containing 1-6 or 1-3 carbon
atoms ~lu~e, unless specified otherwise, straight-
-chain a~ branched-chain hydrocarbon groups containing
1-6 or 1-3 carbon atoms such as methyl, ethyl, propyl,
S isopropyl, butyl, isobutyl, tert.butyl and the like.
The term "l~wer alkyl" preferably means an alkyl
group containing 1-6 carbon atoms.
The alkenyl and alkynyl groups containing 2-6
carbon atoms include unsaturated straight-chain and
branched-chain hydrocarbon groups containing 2-6
carbon atoms such as allyl, butenyl, isobutenyl, pentenyl,
isopentenyl and the like as well as propargyl, butynyl,
isobutynyl, pentynyl and the like. Especially preferred
alkynyl groups are l-propynyl, butynyl and isobutynyl.
The term "halogen" includes fluorine, chlorine,
bromine and iodine, preferably chlorine, bromine and
iodine.
The cycloalkane ring preferably contains 4-7 carbon
atoms, especially 4-6 carbon atoms.
0
-- 6 --
The term "aryl" includes, in particular, phenyl,
wAich may be substituted with 1-3 lower alkyl groups,
as well as naphthyl. The lower alkyl groups can be
the same or different.
S Preferred heteroaryl groups are the pyridyl,
imidazolyl, thiazolyl and thiophenyl groups.
Preferred compounds of formula I are those in
which Rl represents a methyl or ethyl group, those
in which R2 represents a methyl, ethyl or phenyl group,
those in which R3 represents a chlorine atom or a
trifluoromethyl group, those in which R4 represents
a hydrogen atom and those in which R5 represents a
h ~ ogen atom. The compounds of formula I in which
R1 and R2 together with the car~on atom to which they
are attached form a cycloalkane ring which may be
substituted with alkyl are also preferred.
Especially pre~erred compounds of for~ula I are:
O
- 7 -
2-L p-[(a,a,a,-Trifluoro-p-tolyl)oxy3phenOX~7-
-propionic acid L [ (isopropylideneamino)oxy]methyl_7
ester and
2-[p-(p-chlorophenoxy)phenoxy}propionic acid
S L [ (isopropylideneamino)oxy~methyl_7ester.
Examples of other compounds of formula I are:
2-[p-(2,4-Dichlorophenoxy)phenoxy ]-propionic
acid ~ [(isopropylideneamino)oxy~methyl_7ester,
2-[p-(2,4-dichlorophenoxy)phenoxy}-propionic
acid L t (-methyl-benzylideneamino)oxy~methyl_7ester,
2-L p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy_7-
-propionic acid L [ (sec.butylideneamino)oxy]methyl_7
ester,
2-/ p-[(a,a,a-trifluoro-p-tolyl)oxy~phenoxy_7-
-propionic acid / [(1-pentyl-hexylideneamino)oxy]methyl_7
ester,
2-~ p-~(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid / ~(1,3-dimethyl-2-hutylideneamino)oxy~-
methyl 7 ester,
~.
,
0
- 8 -
2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy~phenoxy 7-
-propionic acid ~ [(a-methyl-benzylideneamino)oxy]-
methyl_7 ester,
2-~ p-~(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid / ~(cyclohexylideneamino~oxy]methyl_7
ester,
2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy_7-
-propionic acid ~ ~(cyclopentylideneamino)oxy]methyl 7
ester,
2-~ p-~(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid ~ ~(cycloheptylideneamino)oxy]methyl_7
ester,
2-/ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid ~ ~(benzylideneamino)o.xy]methyl_7 ester,
2-~p-(p-bromophenoxy)phenoxy]-propionic acid
[(isop~opylideneamino)oxy]methyl 7 ester,
2-~p-(p-nitrophenoxy)phenoxy]-propionic acid
~ E ( isopropylideneamino)oxy]methyl_7 ester
and ~ower al~yl-substituted derivatives of the afore-
mentioned cyclopentylideneamino, cyclohexylideneamino
and cycloheptylideneamino compounds.
O
- 9 -
Especially preferred are the D-isomers of the
compounds of formula I and, consequently, the D-isomers
of the aforementioned individually named compounds.
In embodiment (a) of the foregoing process for
the manufacture of the compounds of formula I, a salt
of an acid of formula II is reacted with a compound
of formula III.
The term "salt of an acid" means, for example, an
alkali metal salt such as, for example, the sodium,
potassium or lithium salt, an alkaline ear~h metal
salt such as, for example, the magnesium, calcium or
barium salt, a salt of an organic base such as, for
example, a mono-, di- or trialkylammonium salt or a
pyridinium salt, or the ammonium salt.
The leaving group denoted by X in the compounds of
formula III is, for example, a chlorine, bromine or
iodine atom, a tosyloxy or mesyloxy group, a hydroxyl
group in free or esterified form or one of the following
groups:
o
-- 10 --
~ N - R8 y ~
wherein R7, R8 and R9, which can be the same or
different, each represent an alkyl group, especially
an alkyl group containing 1-6 carbon atoms, or two of
S - R7, R8 and R9 together also form a C4-C7-alkylene
group and Y ~ represents an anion (e.g. a chlorine,
bromine, iodine, hydroxyl or sulphate anion);
R10
~S/ y~
R
wherein R10 and Rl , which can be the same or different,
each represent an alkyl group, especially an alkyl
group containing 1-6 carbon atoms, and Y ~ has the
significance given earlier;
ll'~'~S'~O
)
Il n 12
wherein R12 represents a lower al~yl, an-aryl or a
heteroaryl group and n stands for 1 or 2.
The reaction of a salt of an acid of formula II
with a compound of formula III is preferably carried
out in a suitable inert solvent at about -10C to
220C, preferably at room temperature or at an elevated
temperature. An especially preferred temperature range
lies between 20C and 70C. The reaction is carried
out, for example, in the presence of an inert solvent
such as benzene, toluene, petroleum ether,
dimethylformamide, tetrahydrofuran, acetonitrile,
N-methyl-2-pyrrolidone, tetramethylurea, dimethoxyethane,
diglycol dimethyl ether or hexamethylphosphoric acid
triamide.
In embodiment (b) of the present process for the
manufacture of compounds of formula I, a compound of
formula IV is reacted with a compound of formuLa V or
with an alkali metal salt thereof ln a manner ~nown per
se.
1~25~0
- 12 -
The leaving group denoted by Z in compounds of
formula IV is, for example, one of the leaving groups
already given above for X, or a hydroxyl
group activated by reaction with triphenylphosphine
and azodicarboxylic acid or an ester thereof, especially
azodicarboxylic acid diethyl ester ~see, e.g. 3ull. Chem.
Soc. Japan 46, 2833 (1973) or Angew. Chem. 88, 111 (1976)].
The reaction according to embodiment (b) is
conveniently carried out in an inert organic solvent
such as a hydrocarbon (e.g. benzene or toluene), an
ether (e.g. diethyl ether, tetrahydrofuran or
dimethoxyethane) or hexamethylphosphoric acid triamide.
The temperature and pressure are not critical, the reaction
preferably being carried out at a temperature between
lS -20C and the reflux temperature of the reaction mixture,
preferably between -10C and 30C.
In embodiment (c) of the present process for the
manufacture of compounds of formula I, a compound of
formula VI is reacted with an oxime of formula VII in
the presence of a base (e.g. an alkali metal carbonate3.
ll~Z540
In this embodiment, a cQmpound of fonm~a VI can be diss~lved
in an inert organic solvent such as a chlorinated
hydrocarbon ~e.g. dichloromethane, chloroform, carbon
tetrachloride or trichloroethane), an ether or an ether-
liks compound (e.g. tetrahydrofuran, diethyl ether,diisopropyl ether, dimethoxyethane or dioxan), an
aromatic hydrocarbon (e.g. benzene, toluene or xylene),
dimethylformamide, dimethyl sulphoxide or hexamethyl-
phosphoric acid triamide and thereafter the oxime of
formula VII (e.g. in the form of an alkali metal salt) is
added. The reaction is generally carried out at a
temperature between 0C and the boiling point of the
reaction mixture, preferably at a temperature between
0C and 50C. The reaction is normally completed after
a short time (e.g. a few minutes). The reaction mixture
is conveniently poured into water and extracted with an
organic solvent (e.g. ethyl acetate). The residue obtained
after evaporation is, if necessary, purified by re-
crystallisation or chromatography.
Formula I includes not only racemic compounds ~ut
also optical isomers, since an asymmetric carbon atom
~o
is present in the a-position to the carbonyl group.
The ester moiety can contain further asymmetric carbon
atoms. If desired, the racemic compounds can be
separated into dextrorotatory and levorotatory compounds
according to known processes. Such processes are
described, for example, in Industrial and Engineering
Chemistry 60 (8) 12-28. The isomers and the racemic
mixtures all possess herbicidal activity, but the extent
of this activity is different. The D-isomers have the
greatest activity, followed by the racemic mixtures and
then the L-isomers. In connection with investigations
of this type, it has been found that, for example, in
certain experimental procedures the D-isomer of 2-
-/ p-t(a,a,a-trifluoro-p-tolyl)oxy] phenoxy_7-propionic
1~ acid ~ [(isopropylideneamino)oxy]methyl / ester has a
greater activity than the racemic mixture.
The isomers can also be manufactured by synthesis
from corresponding optically active starting materials.
The D-isomers of the compounds of formula I are, as
mentioned earlier, especially preferred and, consequently,
the correspondinq starting materials are also especially
preferred.
0
- 15 -
As a result of the nitrogen-car~on double bond
in the group of the formula
R1
-N ~
~ 2
there are in each case obtained two geometric isomers
(when Rl and R2 have different significances), these
isomers being called the syn- and anti-forms. In
certain cases it is possible to isolate such isomers.
They also form part of the present invention.
The present invention is also concerned with
herbicidal compositions which contain as the active
ingredient one or more compounds of formula I as
defined earlier. These herbicidal compositions
conveniently contain at least one of the following inert
materials: carrier substances, wetting agents, inert
diluents and solvents.
O
- 16 -
The compounds of formula I hereinbefore are
especially suitable for controlling weeds, especially
slender foxtail (Alopecurus myosuroides) and ~ ~ m~
such as, for example, cock's foot (Echinochloa crus-galli),
great foxtail millet (Setaria faberii) and hair-like
millet (Panicum capillare) in cereals, especially barley,
oats and wheat, as well as in rice, cotton, soya, sugar
beet and vegetable plantations. The compounds of
formula I are especially suitable for controlling weeds
in sugar beet plantations. ~hus, for example, 2-
-~ p-~(~,a,a-trifluoro-p-tolyl)oxy~phenoxy_7-propionic
acid / ~(isopropylideneamino)oxy~methyl_7 ester in a
concentration of 1.25 kg/ha possesses sufficient
activity against weeds without, however, damaging the
sugar beet plantations. In general, a concentration of
0.1-6 kg/ha, preferably 0.6-2.0 kg/ha and especially
preferably 1-1.5 kg/ha, is sufficient to produce the
desired herbicidal effect with the compounds of
formula I.
When R3 represents a trifluoromethyl group, the
compounds of formula I can only find limited use in
cereal growing, since they are somewhat phytotoxic.
O
- 17 -
These compounds are, however, especially suitable
for controlling weeds in rice, cotton, soya, sugar
beet and vegetable plantations.
The compounds of formula I are generally insoluble
in water and can be formulated according to any of the
methods which are usual for insoluble compounds.
When desired, the compounds of formula I can be
dissolved in a water-immiscible solvent such as, for
example, a high-boiling hydrocarbon, which conveniently
contains dissolved emulsifiers, so that it acts as a
self-emulsifiable oil upon addition to water.
The compounds of formula I can also be mixed with
a wetting agent, in the presence or absence of an
inert diluent, to form a we~table powder which is
soluble or dispersible in water, or they can be mixed
with the inert diluents to form a solid or pulverous
product.
Inert diluents with which the compounds of formula I
can be formulated are solid inert media, including
pulverous or finely divided solid substances such as,
for example, clays, sands, talc, mica, fertilisers and
the like, such products being present either in the form
5 ~0
- 18 -
of a dust or as materials having a larger particle size.
~ he wetting agents can be anionic wetting agents
such as, for example, soaps, fatty su~phate esters
such as dodecyl sodium sulphate, octadecyl sodium
S sulphate and cetyl sodium sulphate, fatty-aromatic
sulphonates, such as alkylbenzenesulphonates or butyl-
naphthalenesulphonates, more complex fatty sulphonates
such as the amide condensation products of oleic acid
and N-methyltaurine or the sodium sulphonate of dioctyl-
succinate.
The wetting agents can also ~e non-ionic wetting
agents such as, for example, condensation products of
fatty acids, fatty alcohols or ~y substituted phenols
with ethylene oxide, fatty acid esters and ethers
of sugars or polyvalent alcohols , the products which
are obtained from the latter by condensation with
ethylene oxide, or the products which are ~nown as
block copolymers of ethylene oxide and propylene oxide.
0
-` 19 -`
The wetting agents can also be cat~onic wetting agents,
such as, for example, cetyltrimethylammonium bromide and the
like.
The herbicidal compositions provided by the present
invention can also be formulated as aerosols, a co-solvent
and a wetting agent conveniently being used in addition to
the propellant gas, which is suitably a polyhalogenated
alkane (e.g~ dichlorodifluoromethane).
~he herbicidal compositions provided by the present
invention can contain, in addition to compounds of formula I,
synergists and other active ingredients (e.g. insecticides,
a¢aricides, bactericides, other herbicides, fungicides,
plant growth regulators and fertilisers). Such combination
preparations are suitable for increasing the activity or for
broadening the spectrum of activity.
The co~ounds of ~oxmula I can be used in different pro-
poxtions in their variou$ fieIds o~ ~p~lication~ Thus the
present invention provides a method for the control of weeds,
which method comprises treating the locus to be protected
a~ainst weeds, and/or the weeds, with an effective amount of
a compount of formula I as set out above.
0
- 20 -
The herbicidal compositions provided by the
present invention can be formulated in a form which
is suitable for storage and transport. Such forms
can contain, e.g., 2-90 weight percent of one or more
compounds of formula I. These forms can then be
diluted with similar or different carrier materials
to provide concentrations which are suitable for
practical use. In ready-for-use herbi~idal compositions,
there can be present active ingredient concentrations
of 0.05-80 weight percent. The active ingredient
concentration can, however, also be lower or higher.
Depending on the intended use, an active ingredient
concentration of 2-8 weight percent or 50-80 weight
percent is especially preferred.
The starting materials of formulae II, III, IV,
V and VII belon~ to known classes of compounds.
The starting materials of formula VI can be
prepared by oxidising a compound of the general formula
0
- 21 -
R~
R ~ O ~ ~ COOCHz_S-R6 VIII
wherein R3, ~4, R5 and R6 have the significance
given earlier.
me oxidation can be carried out, for example, using
hydrogen peroxide.
The compounds of formulae VI and VIII can be
prepared in analogy to the details given in DOS 2 617 804.
Thus-obtained racemates can be resolved in the customary
manner.
The compounds of formulae VI and VIII in which
R6 represents a heteroaryl group are novel, i.e.
irrespective of whether they are present as racemates
5~0
- 22 -
or in the form of the optical isomers (e.g. the D-
-isomers). When R6 in the compounds of formulae Vl
and VIII represents a lower alkyl group (e.g. a methyl
group), an aryl group (e.g. ~phenyl group or a
halophenyl group),then the corresponding D-isomers
are also novel.
The aforementioned novel compounds of formulae VI
and VIII can be prepared, for example, by reacting the
racemate or the D-isomer of a compound of formula II
with a compound of the general formula
HO-CH2-S-R6 IX
wherein R6 has the significance
given earlier in this paragraph.
This reaction can be carried out in a manner ~nown
per se, advantageously in an inert organic solvent
such as chloroform or dimethyl sulphoxide and in
the presence of dicyclohexylcarbodiimide. ~ thus-
0
- 23 -
-obtained compound of formula VIII can then be oxidised,
for example with hydrogen peroxide, to give a compound
of formula VI.
Especially preferred compounds of formulae VI
and VIII are:
D-2-~p-(p-Bromophenoxy)phenoxy]-propionic
acid methylthiomethyl ester,
D-2-~p-(p-fluorophenyloxy)phenoxy]-propionic
acid methylthiomethyl ester,
D-2-~p-(p-nitrophenoxy)phenoxy3-propionic
acid methylthiomethyl ester and
D-2-~p-(p-trifluoromethylphenoxy)phenoxy~-
-propionic acid methylthiomethyl ester as well as
the corresponding sulphonyl compounds.
The aforementioned compounds of formulae VI and
VIII, especially the D-isomers thereof, are also
valuable as herbicides, since they exhibit a similar
spectrum of activity as the compounds of formula I.
ll ~Z5~0
- 24 -
They can therefore be used for the manufacture of
herbicidal compositions in the same manner as
described earlier for the compounds of formula I.
The D-isomers have the advantage that, in comparison
to the corresponding racemates, they possess, for
example, a lower phytotoxicity on cotton and soya
beans.
0
- 25 -
The following Examples illustrate the present
invention.
I. Manufacture of the compounds of formula I:
Example 1
36 g of 2-~ p-~(,a,a-trifluoro-p-tolyl)oxy]-
phenoxy 7-propionic acid [(methylsulphonyl)methyl]
ester are dissolved in 20 ml of tetrahydrofuran. A
mixture of 0.35 g of acetone oxime sodium salt,
dissolved in 20 ml of dimethylformamide, is added to
this solution and the mixture is stirred at room
temperature for 2 minutes. The mixture is poured
into water, extracted with ethyl acetate and washed
neutral with water. The ethyl acetate is evaporated
and the residue is then chromatographed on 100 g of
silica gel with hexane/ethyl acetate (8:2). The
eluate is evaporated and the residue is recrystallised
from ether/hexene. The resulting 2-~ p-[(a,a,a-
-trifluoro-p-tolyl)oxy~ phenoxy_7-propionic acid
J ~(isopropylideneamino)oxy~ methyl /ester melts at
76-77C.
0
- 26 -
In an analogous manner,
from D-2-~ p-[(a,a,a-trifluoro-p-tolyljoxy]phenoxy 7-
-prop~onic acid ~(methylsulphonyl)methyl3 ester and
acetone oxime sodium salt there is obtained D-2-~ p-
-~(a,a,a-trifluoro-p-tolyl)oxy3phenoxy_7-propionic acid
~ ~(isopropylideneamino)oxy]methyl 7 ester; melting
point 80-85C; [a]D2 = +11.62(c = 1.25~ in chloroform);
from D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]-
phenoxy 7-propionic acid t(methylsulphonyl)methyl3 ester
and acetophenone oxime sodium salt there is obtained
D-2-~ p-~(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid / [(a-methyl-benzylideneamino)oxy]-
methyl_7ester; melting point 63-64C; [a]22= -13.64
(c = 0.75% in chloroform);
from D-2-[p-(p-chlorophenoxy)phenoxy]-propionic
acid [(methylsulphonyl)methyl] ester and acetone oxime
sodium salt there is obtained D-2-[p-(p-chlorophenoxy)-
phenoxy3-propionic acid / ~(isopropylideneamino)oxy3-
methyl_7 ester; n20 =1.5480; [a322 =+ 13.58
(c = 1.93% in chloroform);
0
from 2-[p-(o,p-dichlorophenoxy)phenoxy~-propionic
acid [(methylsulphonyl)methyl] ester and acetone oxime
sodium salt there is obtained 2-[p-(o,p-dichlorophenoxy)-
phenoxy]-propionic acid ~ [(isopropylideneamino)oxy]-
methyl_7 ester; nD =1.5557.
from 2-[p-(o,p-dichlorophenoxy)phenoxy]-propionic
acid t(methylsulphonyl)methyl~ ester and acetophenone
oxime sodium salt there is obtained 2-tp-(o,p-
-dichlorophenoxy)phenoxy]-propionic acid ~ t(a-methyl-
-benzylideneamino)oxy]methyl_7 ester; melting point
66-67C;
from D-2-tp-(p-bromophenoxy)phenoxy]-propionic
acid t(methylsulphonyl)methyl] ester and acetone oxi~e
sodium salt there is obtained D-2-tp-(p-bromophenoxy)-
phenoxy]-propionic acid ~ t(isopropylideneamino)oxy]-
methyl 7 ester; nD = 1.5598; [a]D2 = +11.92
(c = 1.15~ in chloroform);
ll~Z~i40
from D-2-[p-(p-iodophenoxy)phenoxy]-propionic
acid ~(methylsulphonyl)methyl] ester and acetone oxime
sodium salt there is obtained D-2-[p-(p-iodophenoxy)-
phenoxy]-propionic acid / ~(isopropylideneamino)oxy]_
methyl 7 ester; melting point 40-43C; ~a]D2 =+8.60
~c = 0.90~ in chloroform);
from D-2-/ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy_7-
-propionic acid ~(methylsulphonyl)methyl] ester and
cyclopentanone oxime sodium salt there is obtained
D-2-~ p-[(~,a,a-trifluoro-p-tolyl)oxy]-phenoxy_7-
-propionic acid ~ ~(cyclopentylideneamino)oxy]methyl_7
ester; melting point 43-45 C; ~a]D = +7.52
(c = 2.28% in chloroform);
from D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid [(methylsulphonyl)methyl_7 ester and
cyclohexanone oxime sodium salt there is obtained
D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]-phenoxy 7-
-propionic acid ~ [(cyclohexylideneamino)oxy]methyl 7
ester; melting point 71-73C; [a]D2 = ~5.55
~c = 1.49% in ch1oroform);
}O
- 29 -
from D-2-/ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy /-
-propionic acid t(methylsulphonyl)methyl] ester and
cycloheptanone oxime sodium salt there is obtained
D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy~-phenoxy 7-
-propionic acid ~ ~(cycloheptylideneamino)oxy] methyl 7
ester; melting point ca 30C; [a~22 = +6.00
(c = 1.96% in chloroform);
from D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid [(methylsulphonyl)methyl] ester and
3,3,5-trimethylcyclohexanone oxime sodium salt there
is obtained D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]-
phenoxy 7-propionic acid ~ [(3,3,5-trimethylcyclo-
hexylideneamino)oxy]methyl 7 ester; n20 = 1.5062;
[a]D = +6.86 (c = 2.73% in chloroform);
lS from D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy /-
-propionic acid ~(methylsulphonyl)methyl} ester and
benzaldoxime sodium salt there is obtained ~-2-~ p-
-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-propionic
acid ~ [(benzylideneamino)oxy]methyl 7 ester; melting
point 65-66C; [alD = -16.34 (c = 1.60~ in chloroform);
0
- 30 -
from D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy_7-
-propionic acid [(methylsulphonyl)methyl] ester and
ethyl methyl ketoxime sodium salt there is obtained
D-2-l p-~(a,a,a-trifluoro-p-tolyl)oxy]phenoxy_7-
-propionic acid ~ t(sec.butylideneamino)oxy]methyl_7
ester; melting point 38-40C; [a}D2 = + 10.34
(c = 2.36% in chloroform);
from D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy_/-
-propionic acid ~(methylsulphonyl)methyl] ester and
dipentyl ketoxime ~x~ t ~ ~ d~Ed ~2-~(a,a,~
-trifluoro-p-tolyl)oxy]-phenoxy 7-propionic acid
~ ~(l-pentyl-hexylideneamino)oxy] methyl 7 ester;
nD = 1.4913; ~a]D2 = ~11.71 (c = 3.27% in chloroform);
from D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid [(methylsulphonyl)methyl] ester and
methyl (2-methyl-1-propenyl) ketoxime sodium salt there
is obtained D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]-
phenoxy_7-propionic acid ~ [~1,3-dimethyl-2-buten-
ylideneamino)oxy]methyl 7 ester; melting point
52 -54 C; [a~D = -5.7S (c = 0.78% in chloroform~.
}0
Example 2
A solution of 10 g (0.0307 mol) of D-2-/ p-t(Q,a,a-
-trifluoro-p-tolyl)oxy]phenoxy 7-propionic acid in 100 ml
of dimethylformamide is added dropwise while stirring
S to a suspension of l.S g of 55% sodium hydride dispersion
(0.0307 mol) in 20 ml of dimethylformamide. After
completion of the addition, the mixture is stirred
at room temperature until the hydrogen evolution has
stopped. The mixture is stirred for a further lS minutes
and there are added thereto 15 g (0.048 mol) of N-[(iso-
propylideneamino)oxy]-N-methyl-piperidinium iodide and
0.5 g of lS-crown-5 (the polyethylene ether-crown compound
with a 15-ring containing ~ oxygen atoms). After stirring
at 110C for 2 hours, the mixture is poured into 500 ml of
water and extracted three times w~th 300 ml of ethyl
acetate each time. The ethyl acetate extracts are
combined, washed twice with 200 ml of water each time
and then evaporated, the residue being subsequently
recrysta}lised from diethyl etherJn-hexane. There are
o~tained 8,o g of D-2-/ p-~(a,a,a-trifluoro-p-tolyl)oxy~-
phenoxy_~-propionic acid / ~(isopropylideneamino)oxyl-
}V
- 32 -
methyl_/ ester which melts at 85-86C; [a]20 = +11~3
(c = 1.2% in chloroform).
Example 3
1.75 g of L ~-)-lactic acid ~ ~(isopropylideneamino)-
oxy~methyl / ester, 2.65 g of triphenylphosphine and
2.54 g of p-[(a,a,a-trifluoro-p-tolyl)oxy~-phenol are
dissolved at 0C in 10 ml of absolute tetrahydrofuran.
1.75 g of azodicarboxylic acid diethyl ether are added
dropwise to the solution while cooling. After completion
of the addition, the mixture is stirred for 0.5 hour,
then poured into 100 ml of water, extracted twice with
50 ml of water each time, dried over anhydrous sodiium
sulphate and evaporated. The residue is chromatographed
on a 20-fold amount of silica gel with n-hexane/ethyl
acetate (4:1) and the eluate is evaporated. The residue
is crystallised from diethyl ether/n-hexane and there is
obtained D-2-/ p-~( a, a, a- trif}uoro-p-tolyl)oxy~phenoxy ? ~
-propionic acid / [(isopropylideneamino)oxy~methyl_/
ester; melting point 85~C; ~a~D = flO.9 ~c = 1.33%
in chloroform).
0
- 33 -
II. Preparation of the startinq materials:
ExamPle 4
100 g(0.03 mol) of 2-~ p-~(a,a,-trifluoro-p-
-tolyl)oxy]-phenoxy 7-propionic acid and 252 g (3.0 mol)
of sodium bicarbonate are suspended in 2.5 litres of
dimethyl sulphoxide and thereafter treated slowly with
336.5 ml (3.0 mol) of tert.butyl bromide. The mixture
is stirred at room temperature overnight. The mixture,
including the separated thick precipitate, is subsequently
taken up in 5 litres of ethyl acetate. The ethyl
acetate solution is washed twice with 1 litre of water,
dried over sodium sulphate and evaporated. The residue
is chromatographed on a 10-fold amount of silica gel
with hexane/ethyl acetate (7:1) and the eluate is
evaporated. There is obtained 2-l p-[(a,a,a-trifluoro-
-p-tolyl)oxyl phenoxy /-propionic acid [(methylthio)-
methyl3 ester in the form of an oil.
40 g (0.096 mol) of 2-~ p-[( a,a,a-trifluoro-p-
-tolyl)oxy] phenoxy 7-propionic acid ~ (methylthio)-
methyl3 ester are dissolved in 120 ml of acetone/water
- 34 -
(5:1) and treated slowly with 192 ml of a 30% solution
of hydrogen peroxide. 96 ml of ammonium molybdate
solution (35.2 g of ammonium molybdate in 96 ml of
water) are added dropwise to the mixture which is
cooled with an ice-bath. The mixture is stirred at
room temperature for 2 hours. It is .then extracted
several times with ether, the ether extract is washed
with sodium dithionite solution and the solution is
again washed neutral with eight 100 ml portions of
saturated sodlum chloride solution and subsequently
with five 100 ml portions of water. The mixture is
treated with active carbon, filtered and e~aporated.
The residue is recrystallised from methylene chloride/
n-hexane. There is obtained 2-/ p-[(,a,a-trifluoro-
-p-tolyl)oxy~phenoxy_7-propionic acid ~(methylsulphonyl)-
methyl] ester which melts at 87-88C.
In a manner analogous to that described in the
first paragraph of thls Example,
- 35 -
from D-2-~ p-t(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid there is obtained D-2-~ p-[(a,a,a-
-trifluoro-p-tolyl)oxy~phenoxy 7-propionic acid
~(methylthio)methyl] ester; melting point 47-48C;
~a]D2= +31.24 (c = 1.58% in chloroform);
from D-2-[p-(p-chlorophenoxy)phenoxy]-propionic
acid there is obtained D-2-[p-(p-chlorophen~xy)-
phenoxy]-propionic acid [(methylthio) methy~] ester;
melting point 75C; [a]D2= + 50.54 (c = 1.34% in
chloroform);
from 2-~p-(o,p-dichlorophenoxy)phenoxy~-propionic
acid there is obtained 2-~p-(o,p-dichlorophenoxy)-
phenoxy]-propionic acid [(methylthio)methyl] ester;
melting point 54C;
from D-2-[p-(p-bromophenoxy)phenoxyl-propionic
acid there is obtained 2-[p-(o,p-dichlorophenoxy)-
phenoxyl-propionic acid [(methylthio)methyl] ester;
melting point 83-87C; [~322 = +45.52 (c = 1.81%
in chloroform);
0
- 36 -
from D-2-[p-(p-iodophenoxy3phenoxy~-propionic
acid there is obtained D-2-[p-(p-iodophenoxy)phenoxy~-
-propionic acid ~(methylthio)methyl~ ester; melting
point 71-74C; [a]22 = +41.39 (c = 1.43% in
chloroform);
In a manner analogous to that described in the
second paragraph of this Example,
from D-2-L p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy_7-
-propionic acid [(methylthio)methyl] ester there is obtained
D-2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid ~(methylsulphonyl)methyl] ester;
melting point 79-82C; ~3DO = +40 77 (c = 1.66%
in chloroform);
from 2-~ p-~(a,a,a-trifluoro-p-tolyl)oxy]phenoxy_7-
-propionic acid [(phenylthio)methyl ester there is
obtained 2-l p-~(a,a,a-trifluoro-p-tolyl)oxy]phenoxy 7-
-propionic acid ~(phenylsulphonyl)methyll ester;
melting point 89-92C;
0
- 37 -
from D-2-[p-(p-chlorophenoxy)phenoxy]-propionic
acid [(methylthio)methyl] ester there is obtained
D-2-[p-(p-chlorophenoxy)phenoxy]-propionic acid
[(methylsulphonyl)methyl] ester; melting point
81-83C; ~a]D2= +43.42 (c = 1.02% in chloroform);
from 2-[p-(o,p-dichlorophenoxy)phenoxy]-propionic
acid [(methylthio)methyl] ester there is obtained
2-[p-(o,p-dichlorophenoxy)phenoxy3-propionic acid
[(methylsulphonyl)methyll ester; melting point 95C;
from D-2-tp-(p-bromophenoxy)phenoxy]-propionic
acid r (methylthio)methyl~ ester there is o~tained
D-2-[p-(p-bromophenoxy)phenoxy]-propionic acid
[(methylsulphonyl)methyl] ester; melting point
84-87C; [a]D2= +39.20 (c = 1.43~ in chloroform);
from D-2-[p-(p-iodophenoxy)phenoxy3-propionic acid
- [(methylthio)methyl] ester there is obtained D-2-[p-
-(p-iodophenoxy)phenoxy]-propionic acid ~(methylsulphonyl)-
methyl] ester; melting point 121~-123~C; ~a3D2= +37,9t
(c = 2.66~ in chloroform).
l~z~
- 38 -
Example 5
153 ml (1.1 mol) of tert.butyl bromide are slowly
added dropwise to a suspension of 10 g (0.11 mol) of
L (+)-lactic acid and 94.2 g (1.1 mol) of sodium
bicarbonate in 200 ml of dimethyl sulphoxide. The
mixture is stirred for 48 hours, then poured into 1 litre
of water and extracted twice with 100 ml of ethyl acetate
each time. The organic phase is back-washed three times
with 200 ml of water each time and subsequently
evaporated. The crude product is chromatographed on a
20-fold amount of silica gel with n-hexane/ethyl acetate
(4:1) and the eluate is evaporated. There are obtained
5.7 g of L (-)-lactic acid ~(methylthio)methyl] ester;
[a]20 = -39.27 (c = 1.3~ in chloroform).
The foregoing ester can also be obtained by heating
11.2 g of L (+)-sodium lactate, 0.5 g of 1 ~crown-5,
9.25 g of chlorodimethyl sulphide and a trace of sodium
iodide in 100 ml of absolute acetonitrile at the reflux
temperature of the mixture. After 6 hours, the mixture
is poured into water and worked-up in the manner
5'~0
-- 39 --
described in the preceding paragraph. There are
obtained 6.1 g of L (-)-lactic acid ~(methylthio)-
methyl] ester; ~a]20 = _ 3 8.5 (c = 0.69% in chloroform).
2.55 g (0.01 mol) of p-~(~,a,a-trifluoro-p-tolyl)-
ox~lphenol, 1.5 g (0.01 mol) of L-(-)-lactic acid
~(methylthio)methyl~ ester and 2.63 g (0.01 mol) of
triphenylphosphine are placed in 10 ml of absolute
tetrahydrofuran and the mixture is cooled to 0C. While
cooling there is added dropwise 0.011 mol of
azodicar~oxylic acid diethyl ester, the yellow colour
of this ester disappearing during the addition. The
mixture is then stirred at room temperature for 30
minutes, poured into 100 ml of water, extracted twice
with 50 ml of ethyl acetate each time and the organic
lS phase is washed neutral with water. The ethyl acetate
solution is then evaporated, the residue is chromatographed
on a 20-fold amount of silica gel with n-hexane/ethyl
acetate (9:1) and the eluate is evaporated. After
crystallisation from diethyl ether/n-hexane, there are
obtained 2.1 g of D-2-/ p-~(a,~ trifluoro-p-tolyl)oxyl-
phenoxy 7-propionic acid ~(methylthio)methyll ester;
meltins point 52C; ~a~20 = +46.87~ (c = 0.65% in
chloroform).
- 40 -
Example 6
To 100 ml of 36% formalin at 10C are added dropwise
while cooling 100 ml of piperidine and t~ereupon
73 g of acetone oxime as well as 75 g of potassium
carbonate. The mixture is stirred at room temperature
overnight, then taken up in ethyl acetate and the
aqueous phase is separated. The organic phase is
evaporated, the residue is taken up in acetone and
treated dropwise while cooling with 6S ml of methyl
iodide, whereafter the product slowly crystallises out.
After a further 10 hours, the product is filtered off.
There are obtained 291 g of N-[(isopropylideneamino)oxy]-
-N-methyl-piperidinium iodide; melting point 132-133C.
Example 7
1.1 g of sodium lactate, 3.5 g of N-[(isopropylidene-
amino)oxy~-N-methyl-piperidinium iodide and 0.1 g of 1 ~
-crown-5 in 10 ml of diglycol dimethyl ether are heated at
110C under nitrogen for 4 hours. The mixture is then
0
- 41 -
poured into 50 ml of water and extracted three times
with ethyl acetate. The organic phase is washed four
times with water and subsequently evaporated. After
chromatography of the residue on a 10-fold amount of
silica gel with n-hexane/ethyl acetate (1:1) and
evaporation of the elua~e, there is obtained 0.35 g of
L (-)-lactic acid ~ ~(isopropylideneamino)oxy3methyl_7
ester; [a]20 = -1.2 (c = 1.50% in chloroform).
I}I. Formulation Examples-
ExamPle 8
- An emulsifiable concentrate is produced by mixing
the following ingredients with one another:
Compound of formula I S00 g
Condensation product of an alkylphenol
and ethylene oxide; calcium dodecyl-
benzenesulphonic acid 100 g
Epoxidated soya oil with an oxirane
oxygen content of about 6% 25 g
Butylated hydroxytoluene 10 g
0
- 42 -
This mixture is made up to l litre with xylene.
Example 9
The active ingredient of formula I, for example
2-~ p-[(a,a,a-trifluoro-p-tolyl)oxy~phenoxy_7-propionic
acid ~ ~tisopropylideneamino)oxy]methyl 7 ester
(compound A ~n the following Table ) is dissolved in
acetone to give a 2% solution of active ingredient.
Shortly before the beginning of the experiment the
solution is diluted with water to provide the desired
concentration, which in the present experiment is 312 g/ha.
(When an insoluble active ingredient is used, spray
powders which contain kaolin as the inert diluent are
formulated.1
The test plants are sprayed in a greenhouse with
the formulated active ingredient, a 16 hours day being
simulated by means of mercury vapour lamps. 3 weeks
after the spraying the plants are examined for the
effects which have occurred; i.e. the % necroses are
determined, with 100% necrosis corresponding to a
complete destruction of the plant. Solvent effects,
0
- 43 -
as far as present, are compensated by means of the
"Abbott formulan. The results are compiled in the
following Table.
Table I (% necrosis)
S Active ingredient Dosage Alopecurus Digitaria Avena
g/ha myosuroides floridana fatua
Compound A 312 100 100 100
A = 2-/ p-~(a,a,a-Trifluoro-p-tolyl)oxy]phenoxy_7-propionic
acid ~ [(isopropylideneamino)oxy]methyl_7 ester.
Example 10
Table II
% Necrosis in cotton var. Stoneville 7A
kg/ha Compound A Compound H
1.25 0 22
0.62 0
_ _
}0
- 44 -
Formulation: Active ingredient250 g/l
NMP 300 g/l
Tensiofix B 7425100 g/l
Phenylsulphonate CA 25 g/l
Shellsol ABad 1000 ml
Wetting agent: 0.08~ of Nonoxynol
Growth staqe
at treatment: 2 leaf stage
SpraY volume: 1000 l/ha
ApPraisal: 10 days after treatment
Location: Greenhouse
Compound A see Example 9
Compound H = D-2-[p-(p-Trifluoromethylphenoxy)phenoxy]-
-propionic acid methyl ester.
Example 11
Table III
% Necrosis in soYa beans var. ~ood
0
- 45 -
¦kgo/hagae ¦ Compound A ¦
1.25 0
0.62 0
Formulation: Active ingredient 250 g/l
NMP 300 g/l
Tensiofix B 7425100 g/l
Phenylsulphonate CA 25 g/l
Shellsol ABad 1000 ml
Wettinq aqent: 0.08~ of Nonoxynol
Growth stage
at treatment: 2 trifoliate leaf
SpraY volume: 1000 l/ha
Appraisal: 2 weeks after treatment
Location: Greenhouse
Compound A see Example 9.
The notations NMP, Tensiofix B 7425, Phenyl-
sulphonate CA, Shellsol AB and Nonoxynol used in
Examples ~0 and 11 have the following significance:
0
- 46 -
NMP: N-methyl-2-pyrrolidone,
Tensiofix B 7425: Emulsifier consisting of
60 parts of a block polymerisate of ethylene oxide
and propylene oxide, 20 parts of the calcium salt of
a branched-chain dodecylbenzenesulphonic acid and 20
parts of a solvent mixture of isobutanol and C10-
-alkylbenzenes.
Phenylsulphonate CA: Mixture of 70 par~s of the
calcium salt of a branched-chain dodecylbenzenesulphonic
acid and 3~ parts of a solvent mixture of isobutanol and
C10-alkylbenzenes .
Shellsol AB: Solvent consisting of a mixture of
C10-alkylbenzenes.
Nonoxynol: Condensation product of nonylphenol and
ethylene oxide.
