DE2416930A1 - PROCESS FOR THE PREPARATION OF SUBSTITUTED 2-CHLORO-4-ALKYLAMINO-6- (1'CYANALKYLAMINO) -1,3,5-TRIAZINEN OR SUCH HERBICIDAL PREPARATIONS CONTAINED - Google Patents

Description

DR. STEPHAN G. BESZEDES
PATENT ADVOCATE

DAHHAU at MÖNCHEN

BOX 1168

AM HEIDEWEG 2

TIILEH KO N: DACKAU 43

Munich 150S bank account Mr. 90 637 bul eier district and otadtsparkassa Dachaiilnüersdorf

P 683

Describe i bu η

for patent application

NÖVENYVEDELMI ΚϋΤΑΤο "TJTTEZET

Budape st, Ung am

and

NITROIiEMIA IPARTELEPEK Füzfogyartelep, Hungary

concerning

Process for the preparation of substituted 2-chloro-4-alkylamino-6- (1 '-cyanallcylainino ) -1, .5 , 5-triazines or such herbicidal preparations containing them

The invention relates to a new process for the preparation of substituted 2-chloro-4-alkylamino-6- (1'-cyanalkyiamino) - -1,3? 5-triazines of the general formula

2 -

409843/1136

· ^Ε 1

Eq

I,

■ ir - ο - on

where R,

for hydrogen or an alkyl radical with 1 to 3 carbon atoms and

R ₂

R ₅ and

independently of one another in each case an alkyl radical having 1 to 3 carbon atoms mean,

which are effective as herbicides, or herbicidal preparations containing them.

The compounds of the formula I are known, for example from the Hungarian patent 156 467 · 2-chloro -4 ·, 6- (bis-alkylamino) -1,3,5-triazines, which have a 1'-cyanoalkylamino side chain have, were first used by Ubrizsy and Matolcsy (Acta Agron. Acad. Sci. Hung. 11, 173 to 182 [1961j)

409843/1136

7th

". It was recognized by the authors that the Introducing the Cyangruppo for those who work with seed rotation Agriculture extremely disadvantageous persistence or persistence extending over 2 to 3 years the 2-halo-4,6-bis (alkylainino) -1,3 »5-triazines im Soil can be eliminated.

The herbicidally active triazine derivatives having a cyanoalkylamino side chain are used during the cultivation period of the sown plant, for example the maize, are completely degraded, so they are no longer present in the soil. Therefore no phytotoxic effect is exerted on the following seed.

Among the triazines containing a cyanoalkylamino group have those compounds in which the nitrogen of the amino group is bonded to a tertiary carbon atom, the attained great practical importance.

These compounds are prepared according to the prior art in such a way that cyanuric chloride in the presence of a Brought acid acceptor with the corresponding aminonitrile to react and then the one having a cyanoalkylamino group Reaction product in the presence of an acid acceptor with an alkyl or dialkylamino group Connection is implemented.

The disadvantage of this process is that it starts with 1-aminonitriles, which are difficult to prepare. For example, the for preparing a 2-chloro-4-alkylamino-6- £ (1-cyano ^f) - (1'-methyl) -äthylaminoj-1,3 '5 ~ triazines required 1-Aminoisobutyronitril in the V / else obtained that the acetone cyanohydrin formed by the reaction of acetone and hydrogen cyanide is treated with dry ammonia.

409843/1136

The Acetoncyanhydriii can after. Cox and Stormont (Organic Syntheses Coll. Vol. II, 7) are produced in such a way that that a 40% sulfuric acid is added to a mixture of an aqueous sodium cyanide solution and acetone with cooling , the organic phase consisting of acetone cyanohydrin "is separated off and the precipitated sodium bisulfate is separated off and washed with acetone, whereupon the acetone used for washing is combined with the aqueous phase and with ether is extracted, the ethereal extract is added to the separated acetone cyanohydrin and the phase thus obtained is dried then the ether and acetone are distilled off and the residue is subjected to vacuum distillation. the Yield is 77 to 78%.

According to Wagner and Baizer (Organic Syntheses Coll. Vol. Ill, 324-) the acetone cyanohydrin can be prepared in the V / eise that an aqueous sodium bisulfite solution with cooling Acetone and then an aqueous sodium cyanide solution is added, whereupon the upper phase containing the acetone cyanohydrin separated and dried over sodium sulfate. The yield is 70%.

According to Bucherer and Steiner (J. Prakt. Chem. 2 140, 308 £ 1964]), acetone cyanohydrin can be converted into 1-aminoisobutyronitrile in the same way be reacted so that the acetone cyanohydrin is saturated with dry ammonia gas and then the aminonitrile extracted with ether, dried and distilled under vacuum. The yield of this reaction is 64%, which is one Crude yield of 45 to 50%, based on the starting materials Acetone and sodium cyanide.

According to Clarke and Bean, 1-aminoisobutyronitrile can be used . (Organic Syntheses Coll. Vol. II, 29 to 30) also directly starting from acetone are prepared in such a way that a mixture of acetone is added to an aqueous ammonium chloride solution

- 5 -409843/1136

■ γ *

and ether were added and the reaction mixture is then added under cooling "at temperatures below 1O ⁰ G with an aqueous sodium cyanide solution, separated, the etheric Acetoncyanhydrinlosung thus obtained, the aqueous phase extracted with ether, the ether distilled off, the residue is dissolved in methanol and the solution with saturated dry ammonia gas and left to stand for 2 to 3 days, whereupon the excess ammonia is removed by passing air through and the methanol is distilled off.

The processes described are disadvantageous because of their inconvenience and only give poor yields. Further it is disadvantageous that the 1-aminonitriles are easily decomposable and compounds are very moisture sensitive, so that they can be handled and stored dry and so soon must be consumed as possible.

In attempts to remedy the above shortcomings, it has now surprisingly been found that the containing a 1'-cyanoalkylamino group as a side chain 1,3,5-Triazines can be prepared in the V / eise that not from the corresponding 1-aminonitriles, but from their starting materials, namely alkali metal cyanides, ammonium salts and the corresponding ketones or ketone cyanohydrins and ammonia, is assumed and that in the reaction mixture 1-aminonitrile formed in situ without prior isolation is made to react with the cyanuric chloride.

The invention therefore relates to a process for the preparation of substituted 2-chloro-4-alkylamino-5- (1'-cyanoalkylamino) -1,3 »5-triazines the general formula

- 6 A09843 / 1136

Cl

B.

R-

υ - σ - CK

ι ι

MR,,

I,

where R,

represents hydrogen or an alkyl radical having 1 to 3 carbon atoms

, R ₇ and

independently of one another in each case an alkyl radical having 1 to 3 carbon atoms mean,

or herbicide preparations containing such using cyanuric chloride as a starting material, which is characterized in that

a) an alkali metal ;? an id in aqueous solution and an ammonium salt in aqueous solution or ammonium cyanide, optionally prepared in situ in aqueous solution, a ketone of the universal

409843/1136

~ 7 -

common formula

Il

C "D TT

- K /, JLx

wherein R ^ and R ₂ ^ are as defined above, and cyanuric chloride are mixed with one another in any order and the mixture is neutralized by adding a base, the temperature being kept below 5 ° C, or

b) a ketone cyanohydrin in a manner known per se the general formula

HO-C-CN III

wherein R, and R. are defined as above, in a ketone of the formula II, wherein R, and R _{1 are} as defined above, dissolved and passed into the solution at temperatures below 30 ⁰ C gaseous ammonia, then the reaction mixture a Solution of cyanuric chloride in a ketone of the formula II, in which R, and R ^ are as defined above, added and the reaction mixture is neutralized at temperatures below 45 ° C by adding a base.

- 8 409843/1136

and to the reaction mixture obtained according to a) or b) without prior Separation of the reaction product for converting it in a manner known per se, an amine of the general formula

N-H IV

wherein R ^ and Rp are as defined above, is added, if appropriate, the excess of the ketone of the formula II, in which R ₅ and R ^ are defined as above, is removed, and the reaction product is separated off, whereupon this optionally without prior isolation in is converted into a, preferably liquid, herbicidal preparation, in particular an emulsion concentrate, in a manner known per se with customary carriers and / or auxiliary substances.

The process according to the invention is surprising, since the 1-aminonitrile would otherwise be formed under reaction conditions does not form in sufficient quantity, work is being carried out. In the Clarke and Bean method discussed above, forms For example, through the reaction of ammonium chloride, sodium cyanide and acetone, first acetone cyanohydrin, which is only converted to 1-aminoisobutyronitrile by saturation with ammonia gas v / can earth. In the process according to the invention, however, under reaction conditions that are otherwise with those described by Clarke and Bean are identical to the 1-aminoisobutyronitrile immediately without treatment with ammonia gas educated. , This is likely due to the fact that in ketone cyanohydrin, aminonitrile, ammonia and water, However, predominantly ketone cyanohydrin-containing equilibrium system the equilibrium to the same extent as the aminonitrile is consumed by the reaction with the cyanuric chloride, shifts in the direction of the aminonitrile (upper arrow):

- 9 _ 409843/1136

OH,
I ³ + NH, CH ₅ HO - C-CN H ₂ N - C - CN I.
CH,
O CH ₅

The method according to the invention enables all the deficiencies listed in all known methods to be remedied, an increase in the yield, a reduction in the number of process steps and a reduction in the amount necessary for production Expenditure of time.

According to an expedient embodiment of the process according to the invention, this is first carried out, if appropriate in situ produced, ammonium cyanide or alkali metal cyanide and ammonium salt in aqueous solution with the ketone of Formula II, in which R and R are as defined above, for the reaction brought and then the reaction mixture without separation of the reaction product with the cyanuric chloride in solution in the ketone of the formula II, in which R and R are as defined above are implemented.

According to a particularly advantageous embodiment of the The method according to the invention can be proceeded as follows. Cyanuric chloride is dissolved in the corresponding ketone and the solution, with cooling, an aqueous solution containing an alkali metal cyanide and containing an ammonium salt. The ammonium cyanide which forms in the aqueous solution occurs with it the ketone acting both as a solvent and as a starting material in reaction and the 1-aminonitrile formed in the process reacts with the continuous addition of an acid acceptor with the cyanuric chloride to form the 2,4-dichloro-6- (1'-cyanalkylamino) -1,5 »5-triazine in question. The reaction product can be obtained by adding an alkylamine and an acid acceptor per se

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- ίο -

"known way to the desired 2-chloro ~ 4-alkylamino-6- - (1'-Cyanalkylamino) -1,3j5-triazine are implemented.

The "procedure can also be carried out in the manner that the solutions of the ammonium salt and the alkali metal cyanide are added separately to the cyanuric chloride solution.

The ketone of the formula II, in which R ^ and E _{/ (} _ are as defined above, is preferably used as solvent in excess.

The method according to the invention can also be carried out without using a substantial excess of ketone as a solvent. For example, during manufacture of 2-chloro-4-äthylajnino-6- £ (1'-cyan) - (1'-methyl) -äthylaminoj -1 , 3 »5-'briazine an aqueous suspension of cyanuric chloride under Only an equivalent amount of acetone can be added instead of an acetone cyanuric chloride solution. In this However, the yield is generally lower.

According to a special embodiment of the invention Process for the preparation of 2-chloro-4 ~ äthylamino-6-Γ (1'-cyano) - (1'-methyl) -äthylaminoj-1,3,5-triazine are used as Ketone of the formula II acetone and, as the amine of the formula IV, ethylamine used and used for neutralizing and as an acid acceptor, an aqueous sodium hydroxide solution. Than others Possibility to produce 2-chloro-4 ~ ethylamino-6- -jj (i '-cyan) - (I' -methyl) -äthylaminoj-1,3,5-triazine can be used as Ketone cyanohydrin of the formula III and acetone cyanohydrin as an amine of the formula IV ethylamine can be used.

In the case of the Ve2? Drive according to the invention, the end product separates containing ketonic solution from the aqueous solution containing the inorganic by-products. Through this it becomes possible to use the ketonic containing the active ingredient

- 11 409843/1136

Solution immediately, i.e. without prior separation of the active ingredient into herbicidal preparations (e.g. emulsion concentrates) to work up.

The substituted 2-chloro-4-alkylamino-6- (i'-cyanoalkylamino) - prepared by the process according to the invention -1,3 »5-triazines of the formula I can be herbicidal in a known manner Preparations are processed. For the production of these preparations, those customary for such agents are used Carriers and / or auxiliaries used. From the preparations The liquid concentrates, in particular the emulsion concentrates, are particularly preferred because they are produced using those according to the invention Active ingredients arising from the manufacturing process do not need to be grounded in isolation.

The invention is not intended to be limiting in light of the following Examples to be understood are explained in more detail.

example 1

2-chloro-4-ethylamino-6 - [(i'-cyano) - (1'-methyl) - -äthylaminoj -1,3 »5-triazine

18.4 g (0.1 mol) of cyanuric chloride were dissolved in acetone cooled at 180 ° C. under 5 ° C. To the solution, 4.9 g (0.1 mol) of sodium cyanide and 4.8 g (0.11 mol) of ammonium chloride in 28 cubic meters of water were added with cooling and stirring. 4 g (0.1 mol) of sodium hydroxide in the form of a 10% strength aqueous solution were then added with stirring and cooling, it being necessary to ensure that the temperature remained at a value between 0 and 5 ^° C. The mixture was stirred at a temperature below 5 ° for a further 75 hours and then for a further 1 hour without cooling. During this time the pH of the reaction mixture was controlled and, if necessary, by adding

- 12 409843/1136

a 10 ^ aqueous solution of sodium hydroxide kept at 7 to 8. (This generally requires an amount of 6 to 8 g of a 10% sodium hydroxide solution). 4.95 S (0.11 mol) of ethylamine in the form of a 70% strength aqueous solution and 4.4 g (0.11 mol) of sodium hydroxide in the form of a 10% strength aqueous solution were then added to the reaction mixture, the Temperature was kept below 35 ° C. by cooling .. The reaction mixture was stirred for a further 1 hour without cooling and then the acetone was distilled off with stirring at 55 to 65 ° C. The reaction mixture was then cooled and the solid product was separated off, with V / ater and dried. Thus 19 g (78% of theory) of snow-white product having einem.Schmelzpunkt 163-154 ⁰ C were obtained.

Example 2

2-0hlor-4-ethylamino-6 - [(1'-cyano) - (1'-methyl) - -äthylaminoj -1,3,5-triazine

4.9 g (0.1 mol) of sodium cyanide and 4.4 g (0.1 mol) of ammonium chloride were dissolved in 15 cubic meters of water, and 60 cubic meters of acetone were added to the solution with cooling at a temperature below 20 ° C. The mixture was stirred for 2 hours. 18.4 g (0.1 mol) of cyanuric chloride were dissolved in acetone cooled at 180 ° C. under 5 ° C., and this solution was added to the first solution, which consisted of two phases and was constantly stirred, at a temperature below 5 ° C. with stirring. 4 g (0.1 mol) of sodium hydroxide in the form of a 10% strength aqueous solution were then added to the reaction mixture. The mixture was stirred at a temperature below 5 ° C. for a further −κ hour and then for a further 1 hour without cooling. Then 4.95 g (0.11 mol) of ethylamine in

- 13 409843/1136

Form of a 70% aqueous solution and 4-, 4 g (0.11 mol) Sodium hydroxide was added in the form of a 10% strength aqueous solution keeping the temperature below 35 ° C by cooling. The reaction mixture was stirred for 1 hour and

■ χ
then mixed with 140 cm / water. The acetone was either

at 50 to 60 C and under atmospheric pressure or at room temperature and distilled off using vacuum. The residue was cooled and the solid product was separated, washed with water and then dried. So were 21 g (86% of theory) of snow-white product with a Melting point of 163 to 164 ° C obtained.

The crude product was recrystallized from a mixture of acetone and water in the ratio of 1: 2, after which, be Melting point was 166 ° C.

Analysis:

calculated: C = 4-5.2%, H = 5.4-5%, Cl = 14-, 75%, N = 34-, 90%; found: 0 = 4-5.2%, H = 5.59%, Cl = 14x, 53%, N = 35.10%.

Nuclear magnetic

Resonance spectrum: £ CEL (ethyl), triplet

(J = 7.5 Hz): 1.25 ppm; (3H), -CTCH ₃ (i-Pr), singlet: 1.85 PP ^ j (6H), OCH ₂ : 3 _? 55 ppm; (2H) 6 NH: 3.08 and 7.2 ppm.

- 14- -

409843/1136

Example 3

2-chloro-4-ethylamino-6- [(1 · cyan) - (i · methyl) - -äthylamino3-1,3 »5-'triazine containing acetone solution

The procedure described in Example 2 was followed, -but with the difference that after the end of the reaction, the upper phase containing the reaction product the acetonic solution forming the two-phase reaction mixture was separated off and dried with a desiccant and an emulsion concentrate was prepared from the solution by admixing customary auxiliaries.

Example 4-

2-chloro-4-ethylamino-6 - [(1'-cyano) - (1'-methyl) - ethylamino] -1,3,5-triazine

I «) There were 85 g of acetone cyanohydrin at room temperature dissolved in 150 g of acetone. 17 S were added to the solution with constant cooling Introduced ammonia gas, the gas stream was dimensioned so that the temperature of the Reaction mixture did not exceed 30 ° C. the Acetoncyanamine solution obtained in this way was evaporated to room temperature with constant stirring cools.

II.) 184 g of cyanuric chloride were suspended in 1,500 g of acetone with constant stirring and cooling. The solution was cooled to ^{0 ° C.}

- 15 -409843/1136

2A16930

Solution II was then mixed with solution I, making sure that the temperature of the mixture remained at a value of 0 to 5 ° C. 80 g of a 50% aqueous sodium hydroxide solution was slowly added to the mixture. Thereafter, without cooling, 90 g of a 50% strength aqueous jithylamine solution and 80 g of a 50% strength aqueous sodium hydroxide solution were added to the reaction mixture, care being taken to ensure that the temperature remained below 45.degree. The weakly alkaline reaction mixture was left to stand at 40 to 45 ° C. for 1 hour and then poured into 10 1 of water. The precipitated crystals were filtered off, washed on the udder with water and then dried. 212 g of product with a melting point of 163 to 164 ⁰ G were obtained in this way.

Example 5

2 ~ chloro-4-ethylamino-6 - [(1'-cyano) - (1 · -methyl) - -äthylamino]] -1,3 »5-triazine

The procedure described in Example 4 was followed, with the difference that the sodium chloride which separated out from the weakly alkaline mixture was filtered off and 3 liters of water were added to the acetone solution. The acetone was then distilled off. The product separated from the water was washed, filtered off and dried. 225 S of product with a melting point of 163 "to 164 ^° C. were obtained in this way.

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Example 6

2-chloro-4-isopropylamino-6-j_ (1'-cyan) - (1'-methyl) - -äthylaminoj-1,3,5-triazine

The procedure described in Example 2 was used , but with the difference that instead of the aqueous solution of ethylamine 6.2 g (0.105 mol) of isopropylamine are used became. In this way 21.6 g (84% of theory) of product of pale pink color were obtained. After recrystallizing from a A mixture of acetone and water in a ratio of 4: 6 had a melting point of 192 to 193 ° C.

Analysis:

calculated: N = 33.00%, Cl »13.95%; found: N = 33.40%, Cl = 13.77%.

Example 7

2-chloro-4-dimethylamino-6 - ^ (1'-cyano) - (1'-methyl) - -äthylamino3 -1.3 »5

It was worked in the manner described in Example 2, but with the difference that instead of ethylamine 4.95 g (0.11 mol) of dimethylamine were used in the form of an aqueous solution. So 16.2 g (67% of theory) of a white product. After recrystallization from a mixture of acetone and water in the ratio of 4: 6 the melting point was 123 ° C.

Analysis:

calculated: N = 35.80%, Cl ** 15.10%; found: N = 35.11%, Cl = 14.51%.

- 17 -409843/1136

Example 8

2-chloro ~ 4 - ethylaraino-6- [(1'-cyan) - (1'-methyl) - propylamineq] -1,3 »5-triazine

The procedure described in Example 2 was followed, but with the difference that instead of acetone an.-identical amount of methyl ethyl ketone was used. Of the Excess ketone was removed from the reaction equipment using a weak vacuum away. So 23 g (90% of the Theory) Product, which after recrystallization from a mixture of acetone and water in the ratio of 4: 6 had a melting point of 142 to 14-4 ° C.

Analysis:

calculated: N «33.00%, Cl = 13.95%; found: N = 33.37%, Cl = 13.91%.

Example 9

The active ingredients prepared according to the invention could be brought into the form of various preparations. the The composition of an emulsifiable concentrate was as follows;

20% by weight of 2-chloro-4-ethylamino-6 - [(1'-cyano) -

- (1'-methyl) -äthylaminoj -1,3,5-triazine £ 2- (4-chloro-6-ethylamino-s-triazine-2- -ylamino) -2-propiononitrile].

35% by weight of N-methylpyrrolid-2 ~ one 40% by weight of xylene

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5% by weight of a mixture of the calcium salt

of dodecylbenzenesulfonic acid and one Nonylphenol-ethylene oxide condensate

This concentrate could be used immediately by diluting it with water.

The active ingredient could also be brought into the form of cross-linked sprits or sprinkling powders, whereby the content of the active ingredient could be increased by up to 80% be diluted with synthetic silica or kaolin «

Claims 409843/1136

Claims (1)

Pato ηtan sprü c h ο 1.) Process for the preparation of substituted 2-chloro -4 ~ alkylamino ~ 6- (1'-cyanoalkylamino) -1,3,5-triazines der general formula N- Cl ι, l _N -C-ON MR, wherein for hydrogen or one
Is an alkyl radical having 1 to 5 carbon atoms and Rp, R ^ and R ₂ . independently of each other an alkyl radical with Λ to 3
Carbon atoms mean or those containing herbicidal preparations using cyanuric chloride as a starting material, characterized in that one - 20 - 409843/1136 a) an alkali metal cyanide in aqueous solution and an ammonium salt in aqueous Solution or, if appropriate, ammonium cyanide produced in situ in aqueous solution, a ketone of the general formula - R "II wherein R, and R ^ are as defined above, and Cyanuric chloride mixed together in "any order and the mixture neutralized by adding a base, keeping the temperature below 5 ° C or b) in a manner known per se, a ketone cyanohydrin of the general formula HO-C-CK "III wherein R ₅ and R ^ are as defined above, in a ketone of the formula II, in which R ^ and R ^ are defined as above, dissolves and ^{introduces gaseous ammonia into the solution at temperatures below 3O 0} C, then the reaction mixture a Solution of cyanuric chloride in a ketone of the formula II, in which R ₅ and R ^ are defined as above, is added and the reaction mixture is - 21 A09843 / 1136 temperatures below 4-5 C by adding a Base neutralized and to the reaction mixture obtained according to a) or b) without prior separation of the reaction product for converting it in a manner known per se an amine of the general !Formula N-H where R _x and Rp are defined as above, adding, optionally the excess of the ketone of the formula H ₁ where R ^ and R ^ are as defined above, removed and the reaction product is separated off, whereupon this is optionally known per se without prior isolation Conversion with customary carriers and / or auxiliaries into a, preferably liquid, herbicidal preparation, in particular an emulsion concentrate. 2 «) method according to claim 1a) ,. characterized in that the ammonium cyanide, optionally prepared in situ, is first reacted in aqueous solution with the ketone of the formula II, in which R and R _{1 are} as defined in claim 1, and then the reaction mixture is added without separating off the reaction product the Qyanuretilorid in solution in the ketone of the formula II, wherein R, and Rj. are as defined in claim 1, reacts. 3.) Process according to claim 1 a) or 2, characterized in that the ketone of the formula II, wherein R ₇ and R ₁ . as defined in claim 1, in excess - 22 409843/1136 - 22 used as a solvent » 4.) Method according to claim 1a), 2 or 3 for production of 2-chloro-4-ethylamino-6- [_ (1'-cyan) ~ (1 · -methyl) - -athylaininoj-1,3,5-triazine, characterized in that one uses acetone as the ketone of the formula II and ethylamine as the amine of the formula IV and for neutralization and .. as an acid acceptor an aqueous sodium hydroxide solution used, 5.) Process according to claim 1 "b). For the preparation of 2 ~ 0hlor-4-äthylaEiino-6- f (1'-cyan) - (1'-methyl) -äthylaminoj-1 _i 3j5-triazin _t characterized that acetone cyanohydrin is used as the acetone cyanohydrin of the formula III and ethylamine is used as the amine of the formula IV. 409843/1136