Note: Descriptions are shown in the official language in which they were submitted.
- ~07~729
The present invelltion relates to a 1,2,4-triazinone
derivative, a process for l~roducing it and to herbicidal agents
containing said 1,2,4-triazin-5-one derivative as the active
component as well as to tile use of said 1,2,4-triazin-5-one
derivative or of agents containing -them for the control of un-
desired plant growth.
According to the present invention there is provided
a triazinone derivative corres~onding to the formula:
O :,
11 `,
CE~ C
/ ~ / \ (I)
H2C C C N - NH2
11
C2~15 N \ ~ C - SC~13
N
ie 4-amino-6(1-ethyl-cyclo propyl)-3-methylthio-1,2,4-triazin-5-
one.
This application is a divisional application of copend- ~ -
ing application No. 307,630 filea July 19, 1978. In said copend-
ing application ~here is provided a herbicidally active, 1,2,4-
triazin-5-one oE formula I, except being substituted in the 6-
position by l-methyl cyclopropyl.
The product can be prepared by means of a process des-
cribed by Dornow et al (Ber. 97, 2173-79, (1964j). According to
this process an alkyl- or aryl-glyoxylic acid is condensed with
thiocarbohydrazide to a 6-aryl- or alkyl- substituted 4-amino-
3-thiono-1,2l4-triazin-5-one and subsequently reacted by means
of a methylating agent to the 3-methyl-mercapto derivative.
Methyl iodide, methyl bromide or dimethyl sulphate in a basic
medium can be used as methylating agents. However, when apply-
ing this reaction to the production of the compound acc:oxding
-- 1 --
lO~ Z9
to the invention a tertiary alkyl ~mide of the corresponding
glyoxylic acid must be used as the starting material. The
rcaction can be represen-ted by the following equation, wherein
R represents a tertiary alkyl radical containing 4 to 18 carbon
atoms, particularly the t-butyl, t-amyl or t-octyl radical:
CH2
/ \ /
2 C - CO - CON * H2N-NH-CS-NH l~H2
C2H5 R
O
, ~ ,g~
H C Cll C N - NH2
c2~s \ W / = S .,
, ...
H :
CH ll
3 > H C/ ~ C~lC / \ N - NH2
C2H5H C - SCH3
The reactions are carried out preferably in polar sol-
vents, such as methanol, ethanol, dimethyl formamide, dimethyl
sulphoxide, water or mixtures thereof, at temperatures between
0C and the boiling point of the solvent or of the mixtures.
The reactions of the thiocarbohydrazide with the ter-
tiary alkyl arnides of the (l-ethyl-cyclo~ropyl)-glyoxyl:ic acids
are carried out in the presence of an acid, preferably sulphuric
acid, or hydrochloric acid, that is to say, in arnounts corres-
lO~g7Z9
ponding at lcast to the equivalent amount of amide.
The methylation is carried out in a manner known perse, preferably with methyl iodiode or methyl bromide.
r~he (l-ethyl-cyclopropyl)-glyoxylic acid-tert.-al~yl
amides can ~e obtained, for example, by condensation of tlle 1-
ethyl-cyclopropane carboxylic cyanides with a tcrtiary alcollol
or with an alkene in an acid medium. This reaction is carried
out essentially under the conditions of -the so-called "Ritter"
reaction or "Graf-Ritter" reaction (JACS 70, 4045 (1948), JACS
70, 4048 (1948)). Particularly glacial acetic acid or dichloro
me-thane or ether, as for example, dibutyl ether, can be used as
solvents.
The acyl cyanide can be obtained in turn from the
corresponding acyl halide. For cxample, it can be obtained by
means o~ the process oE the German Patent Application P 27 08
183.0 by reaction with CuCII at temperatures between 50 and 180C
in a mixture of approximately 1 to 10 parts by weight of an inert
carboxylic nitrile and approximately 0.5 to 20 parts by weight of
an inert organic solvent, for example, dioxane. According to the
German Patent P 27 08 182.9 this production can also beso carried
out that a mixture of approximately 0.1 to 5 parts by weight of '
alkali metal cyanide and approximately 0.05 to 2 parts by weight
of a copper~ salt is used and that the production is likewise
carried out in the presence of an inert carboxylic nitrile.
The 1,2,4-triazon-5-one derivative according to the
invention which has the formula I afects the growth of plants.
In particular it has excellent herbicidal properties. It
serves primarily for the control of weeds. However, because
of its favourable desicating and defoliating action it can be
used as a harvesting aid in cultures such as cotton and potatoes.
In the control of mono- and di-cyteledonous weeds the
active substance of the formula I exhibits even when applied in
9729
small amo~nts, an excellent herbicidal effect on undesired
vegeta~ion while distinctly sparing a number of useful plant
cultures and in this respect it surprisingly i5 superior to
structurally similar known l,2,4-triazin-5-c)ne cleriva-tives.
This also covers the kinds of weeds which are difficult -to
control.
The tria~inone according to the invention has very
good properties with respect to Gramineae such as millet or
millet-like plants and fox-tail grasses (Alopecurus sp.).
The general e~fec-tiveness of the triazones is known,
for example, that of the compound 4-amino-6-t-butyl-3-methyl-
thio-1,2,4-triazin-5-one. Tlle novel compound differs from the
latter compound primarily in the prcemeryence tcst at average
concentrations in that it ac~5 much more selectively in a num-
ber of us~Eul plant culture~s, as for example, in corn, soybean,
rye, barley and oats, and it also differs by its effectiveness
against Gaiium aparine.
The compound of the present invention can be applied
with equally good results in the usual formulae after the emer-
gence of the plants (postemergently) and particularly preemer-
gently. The amounts used for the active substance accorcling to
the invention vary within wide limits and are surprisingly low
irrespective of purpose and place of applicakion, culture, type
o~ weed and their spread, climatic conditions, etc. In light
soils the triazinone derivative according to the present inven-
tion usually is effective when applied in amounts as low as 0.1kg per hectare. It is preferably applied in amounts of 0.5 to
2.0 kg per hectare. In heavy soils rich in humus and in adsorp-
tive soils higher amounts are required. When applied in amounts
of up to and exceeding 3.0 kg per hectare the total herbicidal
action of the compound outweighs the selective action.
The ~xamples hereafter illustrate the process for pro-
ducing the novel compound having the formula I. The temperature~
lOt797~9
are expressed in deyrees of Celsius.
Example l
a) Production of the l-ethyl-cyclopropane carboxylic cyanide
90.5 g of l-ethyl-cyclopropane carboxylic cllloride are
stirred in l~O ml of acetonitrile ~ trichloroethylene = l:l Wit]
79.3 g of CuCN for 12 hours at 80C. The cooled suspension is
filtered, the filtrate is to-tally concentrated and the residue
is distilled. 65 g of colorless l-ethyl-cyclopropyl carboxylic
cyanide having a b.p.60 mbar of 88C are obtained.
b) Production of the (l-ethyl-cyclopropyl)-glyoxylic tertiary
butyl amide
10 g of a 98% H2S04 are added dropwise to a solution
of 12.3 g of l-ethyl-cyclopropane carboxylic cyanide in 13 g of
t-butanol and 13 ml of methylene chlorid~ within 10 minukes at
O to $C. The solut:Lon is then st~rred Eor ~ hours ~t: room
temperature, whereupon it is mixed with 2 ml of ~I20 and stirred
for further 30 minutes. The pH of the solution is adjusted to
6 with 80 ml of ZnNaOH and the organic phase is separated. After
removing the solvent the residue is crystallized from 50 ml of
petroleum ether (b.p. 40 to 65C) at 50C. Thus, 13.1 g of white
crystals of pure (l-ethyl-cyclopropyl)-glyoxylic tertiary butyl
amide having a melting point of 37.5 to 29C are obtained.
c) Production of the 3-mercapto-4-amino-6-(1-ethyl-cyclopropyl)-
1,2,4-triazin-5-(4H)-one
9.2 g of thiocarbohydrazide hydrochloride are put into
65 ml of H20 and mixed with 12.7 g of (l-ethyl-cyclopropyl)-gly-
oxylic tertiary butyl amide in 65 ml of ethanol. The mixture is
stirred for 8 hours at 80C.
At the same time a portion of the product precipitates.
The suspension is cooled to 20C, mixed with 130 ml of H20 and
stirred for another hour. The precipitated crystals are filtered
off and recrystallized from 50 ml of CH30H. 8 g of colorless
1C~797;~9
crystals consisting of 3-mercapt:o-4-amino-6-(1-ethyl-cyclopropyl)-
1,2,4-triazin-S(4ll)-one having a melting point of 177 to 179~C
are obtained.
d) Production of the 3-methyl-thio-4~amino-6-(1-ethyl-cyclo-
propyl)-1,2,4-triazin-5-(4H)-one
6 g of 3-mercapto-4-amino-6-~1-ethyl-cyclopropyl)-
1,2,4-triazin-5(4~l)-one are dissolved in 14.2 ml of ~N NaOH
and 20 ml of H20 while cold. A solution consisting of 4.8 g
of methyl iodide and 35 ml of CH30H is then added dropwise.
The solution is stirred for three hours at room -temp-
erature, mixed wi-th H20 and then extracted three times with 50
ml of acetic ester. The organic phase is separated, dried and
totally concentrated by evaporation. rrhc rcsiclue (5.7 g) is
recrysta:llLzed from 70 mL oE toluane : petrolc~lm etller = 1:1
~0 to 65C). `
4 g of white crystals having the formula:
O
CH2
/ \ /C\
H C C -C N - NH2
C2H5 ~ D C - SC~I3
are obtained; the melting point is 93 to 95C.
Example 2
~ .
The pre-emergent herbicidal action of the 4-amino-6-
(l-ethyl-cyclo-propyl)-3-methylthio-1,2,4-triazin-5-one was
determined by means of the following tests:
Herbicidal action when applying the active substances prior to
the emergence of the plants (Inhibition of Germination)
In a greenhouse test plants are sown in seed boxes,
that is to say, culture plants as well as mono- and di-cytele-
-- 6 --
~079'729
donous weeds. Lmmediately on completing the sowing, the soilsurface was treated with an aqueous suspension of the active sub-
stance obtained from a 25~ spray powder. I'hree difEerent con
centration series corresponding to 0.5, 0.25 and 0.125 kg of
active substance per hectare were used. The seed boxes were
kept in the g~eenhouse at 22 to 25C and at a relative humidity
of the air of 50 to 70~. After three weeks the test was evalu-
ated and the results were rated according to the following index:
1 = plants not germinated or completely
withered
2 to 8 = int.ermediate stages of damage
9 = plants undamaged (like untreated control '
plants)
___ _______ _____
Test Plant 4-amino-6-tl-ethyl-cyclo-
propyl)-3-methylthio-1,2,4-
tLiaz.in-5-one ..
~ ___~ _ _
g/ha 500 250 125
Avena fatua 1 1 1
Lolium perenne 1 1 1 .
Alopecurus myos. 1 1
Bromus tectorum 1 1 1
Digitaria sanguinalis 1 1
Setaria italica 1 1 1
Echninochloa crus-galli 1 1 1
Sida spinosa 1 1 1
Sesbania exaltata 1 1 1
Amarantus retroflexus 1 1 1 ..
Sinapis alba 1 1 1
Pastinaca sativa 1 1 1
Rumex sp. 1 1 1
Chrysanthemum leuc. 1 1 1
Abutilon sp. 1 1 1
Solanum nigrum 1 1 1
Soybean 3 4
107~72~
~ or the production of herbicidal agents the active sub-
stance is combined with suitable fillers and/or distribution
agents. This is done in a manner known per se by intimately
mixing and grinding the active substance having the general
formula I with suitable fillers, if required while adding dis-
persing agents or solvents which are inert with respect to the
active substances. The active substance can be used in the form
of dusting agents, sprinkling agen-ts, granulates, sheathing gran-
ulates, impregnating granulates, homogeneous granulates, wettable
powders, pastes, emulsions, solutions or aerosols.
For the production of solid processing forms (dusting
agents, sprlnkling agents, yranulates) the active substance is
mixed with solid ~Eillers. For dustlng ~gents ~he particle size
oE th~ Eillers is suitably up to appro~imately 0.1 Tnm~ Eor
sprinkliny agents it is from approximately 0.075 to 0.2 mm and
for granulates 0.2 mm and more. The concentrations of active
substance in the solid processing forms usually is 0.5 to 80%.
Moreover, stabilizing additives and/or nonionic anionics and
cationics, which, for example, improve the adhesiveness of the
active substance on plants and parts thereof (adhesives) and/or
assure a better wettability (wetting agents) and dispersibility
~dispersing agents) can be added to these mixtures.
Active-substance concentrates which are dispersible
in water, wettable pastes and emulsion concentrates constitute
agents which can be diluted with water to any concentration
desired. They consist of active agent, filler, if required,
additives stabilizing the active substance, surface-active sub-
stances and anti-foaming agents and, if required solvents. The
concentration of active substance in these agents is 5 to 80~.
The wettable powders and the pastes are obtained by mixing the
active substance with dispersing agents and powdery fillers in
suitable devices until the mixture is homogeneous, whereupon it
~0~97Z9
is yround. In many cases it is adva~tac3eous to use mixtures of
various fillers. For cxample, silicones, etc., are suitable as
anti-foaming agents. The active substance is so mixed, ground,
screened and strained that the solids in wetted powders do not
exceed a particle size of 0.02 to 0.04 mm and in pastes 0.003
mm. For the production of emulsion concentrates and disperslng
agents, organic solvents and water are used. The solvents must '
be virtually odorless, non-phytotoxic and with respect to ~he
active substance they must be inert and not easily combustible.
Furthermore, the active substance according to the
invention can be applied in the form of solutions. For this
purpose the active substance having -the general formula I is
dlssolved in sui-table organic solvents, solvent mixtures or
water. Th~ solutions should contain the active subqtance in
conc~ntrations ran~ing from 1 to 20%.
Granulate
For the production of a 5% granulate the following
substances are used:
5 parts of active substance according to formula I,
0.25 part of epichlorohydrin,
0.25 part of cetyl polyglycol ether with 8 moles
of ethylene oxide,
3.50 parts of polyglycol ("Carbowax" ~ ),
9.1 parts of kaolin (particle size 0.3 to 0.8 mm).
The active substance is mixed with epichlorohydrin and ' -
dissolved with six parts of acetone, whereupon polyglycol and
cetyl polyglycol ether are added. The solution thus obtained
is sprayed on kaolin. The acetone is subsequently evaporated
in vacuo.
~ettable Powder
For the production of a) a 50~, b) a 25~ and c~ a 10%
wettable powder the following components are used: a) 50 parts
_ g _
~C)7~'7Z9
of active substance accorc~iny to foxmula 1, S parts of sodium
dibutyl naphthyl sulphonate, 3 parts of naphthalene~sulphonie
acids - phenol sulphonic acids - formaldehyde condensate =
3:2:1, 20 parts of kaolin, 22 parts of Champac~ne chalk; b) 25
parts of the actlve subs-tance mentioned above, 5 parts of oleyl-
methyl-tauride-Ma salt, 2.5 par~s of naphtalene sulpllonie acid -
formaldehyde concentra-te, 0.5 part of carboxy-methyl cellulose,
5 parts of neutral kaolin-aluminium silicate, 62 parts of kaolin;
e~ 10 parts of the above aetive substance, 3 parts of a mixture
of the sodium salts of saturated fat-alcohol sulphates, 5 parts
of naphthalene sulphonie aeids - formaldehyde eondensate, 82 _
parts of kaolin.
The above aetive substanee is adsorbed on the eorres-
ponding fillers (kaolin and ehalk) and then mixed and c3round.
A wettable powder of exeellent wettability and suspension prop-
erty is obtained. By diluting these wettable powders with water
suspensions having any desired eoneentration of aetive substanee
ean be obtained. These suspensions ean be used for eontrolling
weeds and undesired grasses in eotton eultures.
Paste
For the produetion of a 45~ paste the following sub-
stanees are used: 45 parts o~ aetive substanee aeeording to
formula I, 5 parts of sodium aluminlum silieate, 14 parts of
cetyl polyglycol ether with 8 moles of ethylene oxide, 1 part
of cetyl polyglycol ether with 5 moles of ethylene oxide, 2
parts of spindle oil, 10 parts of polyglyeol (Carbowax
23 par~s of water.
The aetive substanee is intimately mixed with the
added substanees in suitable deviees and ground. A paste from
whieh suspensions having any desired eoneentration ean be pro-
duced by dilution with water is obtained.
-- 10 --
,.."," ,' . '
~0~797Z9
Emulsion Concentrate
.
For the production of a 10~ emulsion concentrate 10
parts of active substance according to formula I, 15 par-ts of
cetyl polyglycol ether with 8 moles of ethylene oxide and 75
parts of isophorone ~3,5,5-trimethyl-cyclohex-2-en-1-one) are
intimately mixed. This concentrate can be dlluted with water
to suitable concentrations. These emulsions are suitable for
the control of weeds in cultivated plants, as for example, soy-
beans and potatoes, etc.
