SI7710534A8 - Process for the preparation of alpha-cyano-3-phenoxybenzyl-carboxylates - Google Patents

Description

PROCEDURE FOR THE PREPARATION OF ALFA-CYANO-3-PHENOXYBENZYL CARBOXYLATE

TECHNICAL AREAS

The invention relates to a process for the preparation of alpha-cyano-3-phenoxybenzyl-carboxylate, an insecticidally active compound known as synthetic pyrethroids.

According to the International Patent Classification, the invention is classified in C07C 121/75, C07C 120/00.

TECHNICAL_PROBLEM

The invention solves in a new and economical way the problem of producing alpha-cyano-3-phenoxybenzyl-carboxylate by performing the reaction

3-phenoxybenzaldehyde with the corresponding carbonyl halide in the presence of an aqueous solution of alkaline cyanide and a water-immiscible aprotic solvent, and with the addition of a phase transfer catalyst.

STATE_TECHNICS

It is well known, according to D.A.S. No. 2,231,312, that certain sysgetic pyrethroids can be obtained by reaction of substituted cyclopropanecarbonyl halide with 3-substituted benzaldehyde in the presence of an aqueous solution of sodium or potassium cyanide. This produces pyrethroids of the following type:

DESCRIPTION OF THE TECHNICAL PROBLEM SOLUTION WITH EXAMPLES

The invention has now made it possible to obtain an ester of the type given by Formula I, as well as other esters of the type of synthetic pyrethroids, "far more efficiently and in greater yield, by a new process using a special catalyst. That's how it is invented

- esters of the general formula:

* · - * ·. -Ί, · '' provides-tfccSStii & ak. To obtain Rade

Srdja M beogha Phone

R.CO.O

2 * in which R is an optionally substituted alkyl or cycloalkyl group and A is phenoxy, phenylthio or benzyl, and comprises the reaction of a benzaldehyde of the formula:

III with an acyl halide of the formula R.CO.Hal (consisting of Hal bromide or chloride) in the presence of water, water-soluble cyanide, a water-immiscible aprotic solvent, and transfer catalyst phases.

The transfer catalyst may be any reagent capable of accelerating interphase reactions in a two-phase water / organic solvent system.

/ ·

The transfer catalyst may be a thiumium compound, in particular a quaternary thiumium compound of the general formula

R

I

X - R 'I 3 R ^J

2 3 in which X is a nitrogen, phosphorus or arsenic atom, R, R, R 4 and R are each independently an alkyl, aralkyl, alkaryl or aryl group and Y is a monovalent ion, for example a halide, such as chloride, bromide or iodide , iii alkylsulfate such as methylsulfate iii ethylsulfate iii sulfonium compound of the general formula

R

R ¹

R - S - R '<5 6 7 in which R, R and R' are each an alkyl group and Y is a monovalent ion, e.g. a halide such as chloride, bromide or iodide, iii alkyl sulfate such as methyl sulfate or ethyl sulfate. It is preferable that. alkyl groups contain 1 to 18 carbon atoms and aralkyl

3.

Examples of suitable onium compounds are tetra-n-butylammonium bromide, tetra-n-butylammonium chloride, methyl-2-methylphenyl-ammonium chloride, tetramethyl-phosphonium iodide, tetra-n-butylphosphonium-bromide, methylphenyl-ethylphenylarsonyl, methylphenyl-ethylphenylarsonium -2-methylundecylsulfonium ethylsulfate, methyldinonylsulfonium methylsulfate and n-hexadecyldimethylsulfonium iodide. Very good results were obtained with quaternary ammonium compounds.

The yonium compound can be hydroxide or salt and can be used as a functional part of a strongly basic anion exchange resin with a structural part (polymer matrix) and a functional part (ionic group). Of particular importance are polystyrene resins, such as copolymers of aromatic monovinyl compounds, and in particular styrene / divinylbenzene copolymers. The functional part is quaternary ammonium, phosphonium or arsenium groups. Examples of very basic anion-exchange resins that can be used are those derived from trimethyl amines (such as products known as Amberlite IRA 400 ”, Amberlite IRA-401, Amberlite IRA-402, Amberlite IRA-9CO Duolite A- 101-D., Duolite ES-111, Dowex 1, Dowex 11, Dowex 21K and Ionac A-450l, as well as those derived from dimethylethanolamine (such as products known under the trade names Amberlite IRA-4 Amberlite IRA-911. Dowex 2, Duolite A-102-D, Ionac A-542 and Ic A-550) Very good results were obtained with trimethylamine derivatives

Other suitable transfer catalysts are macrocyclic polyethers known as crown ethers. These compounds, together with other preparations, have been described in the literature, for example in Tetrahedron Letters No.18 (1972) pp. 1793-1796, and are usually labeled with respect to the total number of atoms forming a macrocyclic ring together with the number of oxygen atoms in that ring. Such is the macrocyclic polyether whose chemical formula 1,4,7,10,13,16-hexacyclooctadecane is described as 1,8-crown-6. Other examples of macrocyclic polyethers are 3,4-benzo-1, 6,9,12,15,18,21 - heptaoxacyl tricos-3en and 3,4-benzo-1,6,9,12, -en, l8-crowns especially suited.

Other suitable phase transfer catalysts are surfactants. Surfactants are described in Kirk-Othmer, Encycli pedia of Chemical Technology, Second Edition, Volume 19 (1969), Fear 508: 'An organic compound that includes two different molecules in the same molecule

4.

structural groups, one of which is soluble and the other insoluble in water.

Surfactants are preferably non-ionic, such as poly (alkyleneoxy) derivatives obtained by the reaction of higher alcohol, alkylphenol, or fatty acid with ethylene oxide or propylene oxide. Suitable alcohols, alkylphenols or fatty acids contain an alkyl group of 8-20 carbon atoms and the number of alkylenepxy units is in the range of 1-50. A particularly suitable non-ionic surfactant (in the examples given as Dobanol 91-6) is obtained from a mixture of Cg-C ^ n-alkanols and contains an average of six ethyleneoxy units. A non-ionic surfactant may be an alkylbenzene containing an alkyl group in sequence. Suitable alkyl benzenes contain an alkyl group of 8-20 carbon atoms.

The molar ratio of the amount of phase transfer catalyst to the amount of benzaldehyde of general formula III can vary widely, but it is convenient to be from 1: 5 to 1: 500. The use of low molar ratios will require a longer time to complete the reaction, while the use of higher molar ratios naturally increases the price of the product. Therefore, the choice of reaction time and the molar ratio of catalyst to benzaldehyde is arbitrary, and depends on local economic factors. Usually very good results are obtained with molar ratios of 1:10 to 1: 100.

Another advantage of the process according to the invention is that the molar ratio of the amount of acyl halide (R.CO.Hal) to the amount of benzaldehyde is 1: 1 or in low excess. This molar ratio is preferably from 1.1: 1.0 to 1.0: 1.0.

The molar ratio of the amount in water of soluble cyanide to the amount of: aromatic aldehyde is preferably from 1.5: 1 to 1.0: 1.0 and preferably from 1.3: 1 to 1.02: 1.00. Water-soluble cyanide is understood to mean water-soluble hydrogen cyanide. Preferred water-soluble cyanides are alkali and alkaline earth metal cyanides Sodium cyanide is particularly suitable because it gives esters of general Form II for the shortest reaction time.

A suitable temperature at which the process is performed is above 0 °, preferably in the range of 10-50PC. Very good results are obtained at temperatures in the range of 15-40 ° QThis procedure is preferred

5.

that the room temperatures are very appropriate.

Examples of suitable non-miscible aprotic solvents are alkanes or cycloalkanes or mixtures thereof. Specific examples are n-hexane, n-heptane, n-octane, n-nonane, n-decane and their isomers (for example 2-methylpentane, 3-methylpentane, 2methylhexane, 3-methylhexane and 2,4,4- trimethylpentane) and cyclohexane and methylcyclohexane. Alkane-rich gasoline is also very suitable, for example those boiling in the range of 40-65 ° C, 60-80 ° C or 80-110 ° C at atmospheric pressure. Very good results were obtained with n-heptane and cyclohexane.

Other very suitable water-miscible aprotic solvents are aromatic hydrocarbons and chlorinated hydrocarbons, e.g. benzene, toluene, o-, m- and N -xylol, trimethylbenzenes, dichloromethane, 1,2-di-chloromethane, chloroform, monochlorobenzene and

1,2- and 1,3-dichlorobenzene. Very good results were obtained with toluene and xylene.

The process according to the invention can be performed starting from unsaturated or saturated-aqueous solutions of water-soluble cyanide and, in the latter case, in the presence or without water-soluble cyanide. It has been found that with some solvents, the presence of soluble cyanide soluble in water has a positive effect on the yield and reaction time.

The use of alkanes or cycloalkanes in combination with aqueous cyanide solutions without a water-soluble cyanide solution ensures a minimum reaction time. The use of aromatic hydrocarbons or chlorinated hydrocarbons in combination with aqueous cyanide solutions without water-soluble solid cyanide requires a slightly longer reaction time, but this is sometimes more convenient since the reaction mixture thus obtained can be used directly for pesticidal preparations without further separation of the ester. From the solvent. The use of aromatic hydrocarbons and chlorinated hydrocarbons in combination with water-soluble cyanides gives a shorter reaction time. Water-soluble cyanides can be used even in the presence of cycloalkanes.

Suitable reaction times can still be obtained when the molar ratios of the amount of water to the total amount in water of soluble cyanide are greater than 0.05.

6.

Other examples of water-immiscible aprotic solvents are dialkyl ethers and water-immiscible alkanones, e.g. diethyl ether, diisopropyl ether and diisobutyl ketone. Solvent mixtures, e.g. alkanes and aromatic hydrocarbons can also be used, e.g. n-heptane containing up to 10% by weight of benzene and / or toluene.

Group A in general formula II is preferably a phenoxy group as this substituent increases the activity of pyrethroid pesticides.

Group R in the general formula RC (O) Hal is an optionally substituted alkyl or cycloalkyl group. The alkyl group may be straight or branched and preferably contains up to 10 carbon atoms. Alkyl groups preferably contain tertiary or quaternary carbon atoms attached to the group -C (O) Hal. Examples of such alkanoyl halides are 2-methylpropanoyl chloride, 2,2-dimethylpropanoyl chloride and 2-methylbutanoyl bromide. Very good results were obtained with 2-methylpropanoyl chloride. The alkyl group may carry substituents, e.g., hydrocarbonyloxy or substituted phenyl groups, e.g. halophenyl group. Very good results were obtained with

1- (4-chlorophenyl) -2-methylpropyl groups. Preferably, the cycloalkyl group itself contains from 3 to 6 atoms and optionally has as a substituent a group or groups selected from alkyl, alkenyl, haloalkenyl groups, each of which preferably contains up to 8 carbon atoms. Examples of cycloalkyl groups are cyclopropyl, cyclobutyl and cyclohexyl groups. Very good results were obtained with optionally substituted cyclopropanecarbonyl halides, in particular 2,2,3,3-tetramethylcyclopropanecarbonyl halides and 2- (2,2dichlorovinyl) -3,3-dimethylcyclopropanecarbonyl halides. These latter halides may have a cis iii trans structure or may be mixtures of such structures and may be pure optical isomers or mixtures of optical isomers.

Hal substituent in the general formula RC (O) Hal is preferably chlorine or bromine and in particular chlorine.

The process according to the invention can be carried out by the gradual addition of acyl halide to the mixture, preferably by mixing the mixture, other starting compounds (especially suitable when R in the general formula RC (O) Hal represents a 2,2,3,3-tetramethylcyclopropyl group, 2- ( 2,2-dichloro ·

Ί.

vinyl) -3,3-dimethylcyclopropyl group, or 1- (4-chlorophenyl) 2-methylpropyl group. Likewise, any amount of starting material can be combined together with vigorous stirring of the reaction mixture.

The process is of particular importance when it is an aromatic aldehyde

3- phenoxybenzaldehyde and when acyl halide is 2- (4-chlorophenyl) 3-methylbutanoyl chloride, 2,2,3,3-tetramethylcyclopropanecarbonyl chloride, or 2- (2,2-dichlorovinyl) -3,3-dimethylcyclopropanecarbonyl chloride, because the esters thus obtained, οί-ci j ano-3-f enoxybenzyl

2- (4-chlorophenyl) -3-methyl butanoate, N -cyano-3-phenoxybenzyl 22,3,3-tetramethylcyclopropanecarboxylate and ωί-yano-3-phenoxybenzyl 2- (2,2-dichlorovinyl) -3. 3-dimethylcyclopropanecarboxylate, respectively, especially active pesticidal compounds.

The invention is illustrated by examples. All experiments were performed at 23 ° C. The reaction mixtures were vigorously stirred and gas / liquid chromatography analyzes were performed to determine the yields. The reaction mixtures were treated to remove precipitated sodium chloride and solid sodium cyanide, if any, and then the solutions were dried over anhydrous sodium sulfate. Recording of the solution was performed on a vaporizer film at a pressure of 15 mm Hg. All yields were calculated in relation to the starting aromatic aldehyde.

8.

Example I

Preparation of A-cyano-3-phenoxybenzyl 2- (4-chlorophenyl) -3-methylbutanoate in the presence of n-heptane

A 50 ml round bottom balloon equipped with a magnetic stirrer is filled with 10 mmol of 3-phenoxybenzaldehyde, 10 mmol of 2- (4-chlorophenyl) -3-methylbutanoyl chloride, 12 mmol of sodium cyanide, water, catalyst, if used, and 20 ml. .-n-heptane and the mixture thus obtained was stirred. Seven experiments were performed in this way, see Table I.

Table I

1 2 3 4 5 6 Ex. catalyst, no. name quantity in mol% by aldehyde water reaction time, h ester yield% l ¹ '. .. - 1.0. 3 18 86 more than 99 2 methyl-tri-2methyl-heptyl-. ammonium chloride 5 1.0 2 96 3 tetra-n-butylammonium chloride 2 1.0 5 99 4 the same 2 2.0 5 99

tetra-n-butylphosphonium bromide 2 n-hexadecyldime7 1,4,7,10,13,16 hexaoxacyclo-2 octadecane

1.0

1.0

1.0 is not according to the invention

Column 1 in Table I indicates the experiment number ^^ co ^ c ^ pa ^^ catalizer, column. 3-amount of catalyst, .column 4 kc ^ iclhb ^ odebkojapeJE »adds to the starting mix. fceorpαγ '^ f · - * ** b

9.

(except water present in sodium cyanide) and column 5 indicates the reaction time. The yield of the desired ester is given in column 6. Sodium cyanide was completely dissolved.

Example II

Preparation of t-cyano-3-phenoxybenzyl '2- (2,2-dichloro-vinyl) 3,3-dimethylcyclopropanecarboxylate in the presence of n-heptane

A 50 ml round bottom balloon equipped with a magnetic stirrer is filled with 10 mmol of 3-phenoxybenzaldehyde equivalent to the amount of 2- (2,2-dichlorovinyl) -3,3-dimethylcyclopropanecarbonyl chloride, 12 mmol of sodium cyanide, water, catalyst, if used and with 20 ml of n-heptane. The mixture thus obtained is mixed. Six experiments were performed in this way, see Table II. Columns 3, 4 and 5 show the amounts of catalyst, water and acyl chloride. The yield of the desired ester is given in column 7.

Tanirca zr

Ex <br.

catalyst added name water volume mol% pre-ml ma aldehyde.

acyl reaction yield chloride ester time mmol h% methyl-tri2-methylhep-5 1 til ammonium chloride · * tetra-n-bu 'til ammonium 2 1 chloride

Amberlite

IRA 400 ² ) (1 gr) 1

Dobanol 91- ~, £ 3) ² 1

0 10 ·. 2 3 49 0 10.2 1 96

0 '10.5' 1 4 90 99 0 10.5 5 95 0 10.0 2 80

10.0

1,4,7,10,13,16- 2 1.0 hexaoxacyclooctane Dean

A JZ 3 O \ t- t.t

Paja / e 'β. · :;

Cpija Λ1. »K ^ ' ^ΡΑ Λ. TA ^ £ G !, ·, J;

10.

¹ ^ not according to the invention

2) 'trade name for a strong base ion-exchange resin containing a styrene / divinylbenzene copolymer as a polymer matrix and a quaternary ammonium group as an ion-active group. It was used in the form of chloride.

3) the trade name for a non-ionic surfactant formed from a mixture of C _Q -C ₁ alcohols and containing 6 ethyloxy units in proyx x; the alcohol mixture consists of <85% n-alkanol and 15% 2-alkylalkanol.

Example III

Preparation of -cyano-3-phenoxybenzyl 2,2,3,3, -tetramethylcyclopropanecarboxylate in the presence of n-heptane.

The following methods were used to prepare this ester. Under A This example shows that the gradual addition of acyl chloride to the reaction mixture over a period of 0.5 to 2 hours gives a noticeable increase in yield at the end of that period.

Method A

Into a 50 ml round balloon equipped with a magnetic stirrer, 10 mmol of 3-phenoxybenzaldehyde, 1 mmol of 2,2,3,3-tetramethylcyclopropane chloride, 12 mmoles of sodium cyanide, 10 ml of water, catalyst, if used, are introduced. 20 ml of n-heptane. The molar ratio of water to NaCN is 4.64, without solid NaCN. The catalyst was added in an amount of 0.20 mmol. The mixture thus obtained was stirred for 1.5 hours and analyzed.

Method B (gradual addition of acyl chloride)

The balloon used and in the method under A was filled with 10 mmol

3-phenoxybenzaldehyde, 12 mmol of sodium cyanide, 10 ml of nheptane, 1.00 ml of water and 0.20 mmol of catalyst, if used with a molar ratio of water to NaCN equal to 4.64. Introduced into the balloon over a period of 70-75 min. an amount of 10 mmol 2,

3,3-tetramethylcyclopropanecarbonyl chloride of dissolved υ-IO ml and n-heptane · The ester yield was determined at the end of this period εΕΟΓΡΑΛ, 'τΑΚ0Γ. ^ · ^Ηη

TejiOilON OO.

11.

Five experiments were performed in this way. In Table III

the use of a catalyst is shown, the table also giving the desired yield Table III if used. This one ester. - / o-6 J Ex. no. Catalyst Yield Method A of ester in% Method B 1) without 17 4.0 2 1,4,7,10,13,16-Hexaoxacyclooctane Dean 18 97 3 tetra-n-butylammonium chloride 20 98 4 methyl-tri-2-methylheptylammonium chloride 18 96 5 Dobanol 91-6) 44 98

not according to the invention

II II) the explanation for this word is below Table II.

The amounts of catalysts used in Experiments 2-4 were 2%, and in Experiment 5, 10%, calculated according to 3-phenoxybenzaldehyde

The reaction mixture obtained in Experiment 4, method B, was treated and the filtrate was washed twice with 20 ml of 1 M aqueous sodium bicarbonate solution and once with 20 ml of water. The washed filtrate was dried and n-heptane was evaporated from the dried filtrate to give the ester as a pale yellow oil. This oil was dissolved in 2.5 g of methanol at 23 ° C and the resulting solution cooled to -20 ° C to give an ester precipitate. The ester is graded and has a purity of over 98%.

Example IV

/ o f

Preparation of N, -cl iano-3-phenoxybenzyl 2- (4-chlorophenyl) -3-methylbutanoate

Method A (not according to the invention), B and C were compared to obtain the desired ester.

12.

Method k, without phase transfer catalyst.

In a 500 ml round balloon equipped with a mechanical stirrer, 100 mmol of 3-phenoxybenzaldehyde, 100 mmol of 2 (4-chlorophenyl) -3-methylbutanoyl chloride, 120 mmol of sodium cyanide, 10 ml of water (which dissolved all NaCN) and 200 ml were introduced. of n-heptane. After stirring for 45 hours, the mixture was warmed to a temperature between 40 and 50 ° C and processed. The filtrate was washed twice with 50 ml of 1 M aqueous sodium bicarbonate solution, once with 50 ml of water, dried and n-heptane removed. from the dried solution to give the desired compound, the ester in a yield of 99%, a purity of 96%.

Method B, in the presence of onium compounds.

The experiment described in part A of this example was repeated in the presence of 2% m tetra-n-butylammonium chloride, calculated according to 3phenoxybenzaldehyde. After two hours, a yield ester of 99%, a purity of 94%, was obtained.

Method C, in the presence of non-ionic, surfactant happiness.

The experiment described in part A of this example was repeated in the presence of 10% m Dobanol 91-6 (the meaning of this word is given below Table II) calculated according to 3-phenoxybenzaldehyde. After stirring for three hours, the reaction mixture was warmed to a temperature between 40 and 50 [deg.] C., and then proceeded. An amount of 50 ml of ethanol was added (to break the rewarding emulsion) and the filtrate was washed twice with 50 ml of 1 M aqueous sodium bicarbonate solution, once with 50 ml water, dried, and n-heptane was evaporated from the dried solution. to give the ester in a yield of 9 8%, a purity of 97%.

The above results are given in Table IV.

13.

Table IV

Ex. no. Catalyst Reaction time, h Yield of the ester,% Purity of ester,% name quantity,% mol by aldehyde 1 without 45 99 96 .2 tetra-n-butyl ammonium chloride 2 2 99 94 3 Dobanol 91-6 ¹ ^ 10 3 98 97

see Table II for an explanation of this word.

(· '

Example V

Preparation of (-cyano-3-phenoxybenzyl 2- (4-chlorophenyl) -3-methylbutanoate in the presence of different solvents and solid cyanide

A 50-ml round balloon equipped with a magnetic stirrer is filled with 10 mmol 3-phenoxybenzaldehyde, 10.0 or 10.5 mmol 2- (4 chlorophenyl) -3-methylbutanoyl chloride, 12 mmol sodium cyanide 0.02 ml water and 20 ml aprotic solvent. The molar ratio of water to sodium cyanide is 0.105, solid NaCN is present. The reaction mixture was stirred and analyzed. Thirteen experiments were performed in this way, see Table V which gives which solvents are used. Experiments 2,3,4,8 and 9 were performed with 10.0 and the other with 10.5 mmol of 2- (4-chlorophenyl) -3-methylbutanoyl chloride. The petroleum used in Experiment 3 consists of 97 wt.% Alkane and 3 wt. % benzene and at atmospheric key pressure at 62-82 ° C. The esters lagged in the solution during the reactions to Experiments 3 and 4. The reaction mixture obtained in Experiment 4 was processed and the cyclohexane removed from the solvent to give the desired ester as a colorless oil in quantitative presence. Table V also gives the yields of the desired ester. Comparison of yields showed that alkanes and cyclohexane were better solvents.

14.

Table V

Ex. Solvent Reaction time Yield of ester no. h%

1 n-heptane 1.0 more from 99 2 2,4,4-trimethylpentane 1 92 2 99 3 petrol ether 1 91 2 99 4 cyclohexane 1 80 3 more from 99 5 toluene 3 38 24 98 6 dichloromethane 2 34 18 46 7 o-dichlorobenzene 2 59 18 72 8 diethyl ether 3 54 20 91 9 diisobutyl ketone 20 80 10 nitromethane 5 5 21 13 11 1,4-dioxane 18 0 12 Ν, Ν-dimethylformamide 5 5 13 dimethylsulfoxide 2 1 18 0 Example VI “^ ΓΓ Preparation of N, -cyano-3-phenoxybenzyl 2- (4-chlorophenyl) -3- ' methyl-

of butanoate in the presence of solid cyanide

10 mmol of 3-phenoxybenzaldehyde, 10.5 iranols of 2- (4-chlorophenyl) -3methylb.utanoyl chloride, 12 mmol of sodium cyanide, 20 ml of toluene phase transfer catalyst and water were poured into a 50 ml balloon equipped with a magnetic stirrer. The mixture thus obtained is

15.

mixed over different time periods and then analyzed Six experiments were performed in this way, and the results are given in Table VI, which lists which catalysts are used and how much water is added. The catalysts were used in an amount of 0.20 mmol.

Table VI

1 2 . 3 44 5 6 Ex. Catalyst Added Molar Reactionary Prinoi no. water, ml H ₂ O: NaCN ratio time, h ester 1 1,4,7,10,13,16-Hexaoxacyclooctadecane - 0.012 2 20 80 60 91 97 , 2 the same 0.02 0.105 3 100 3 the same 1.00 4.64 2 95 4 98 20 100 4 tetra-n-butylammonium um 0.012 ? bromide ²² 32 5 the same 0.02 0.105. 2 81 18 98 6 the same 1.00 4.64 2 71 22 81 7

For the sake of comparison, the two examples do not have solid sodium cyanide.

The sodium cyanide used consists of particles having a maximum dimension of 0.5 mm and containing 0.44% by weight of water. The molar ratio of water to sodium cyanide was calculated taking into account the water present in sodium cyanide and the added water, if added. For comparison, it can be mentioned that the molar ratio of water to sodium cyanide in saturated aqueous sodium cyanide at 23 ° C is 4.1.

lawyer Rade D ji Mikije

Phone 3B1 / 97O '4 ^r T; .T *' / ···

Ij

'.9

Dos.72289 P-534/77 K 218 YUG 21 February 1984,

APPLICANT'S STATEMENT ON THE BEST KNOWLEDGE WAY TO FIND USE FINDING

Preparation of alpha-cyano-3-phenoxybenzyl 2- (4-chlorophenyl) -3-methylbutanoate

In a 500 ml round balloon equipped with a mechanical stirrer, 100 mmol of 3-phenoxybenzaldehyde, 100 mmol of 2- (4-chlorophenyl) -3-methylbutanoyl chloride, 120 mmol of sodium cyanide, 10 ml of water (which dissolved all NaCN) and 200 were introduced ml of n-heptane. 2% m tetra-n-butylammonium chloride (calculated against 3-phenoxybenzaldehyde) was added. After stirring for 2 h, a yield ester of 99% and a purity of 94% was obtained.

Claims (3)

A process for the preparation of ..xylate of the general formula alpha-cyano-3-phenoxybenzyl-cabro- wherein R is 1- (4-chlorophenyl) -2-methylpropyl, 2- (2,2dihalo.vinyl) -3,3 -dimethylcyclopropyl, or 2,2,3,3-tetramethylcyclopropyl, by reacting 3-phenoxybenzaldehyde with the corresponding carbonyl halide in the presence of an aqueous solution of sodium or potassium cyanide in the middle of a water-immiscible aprotic solvent, in which the process is carried out in the presence of phase transfer catalyst selected from 1,4,7,10,13,16 hexaoxacyclooctadecane, a poly (ethyleneoxy) alcohol derivative, or those compounds of the formula: Ί R ' XR ⁴ . . . 12 3 4 in which X is nitrogen or phosphorus, each of R _t R, R and R is independently (C 1 -C 8) alkyl gTup and Y is chlorine, bromine iii iodine or iii n-hexecdecyldimethyl sulfonium iodide, at a temperature of at about 10-50 [deg.] C., using an alkaline solvent such as n-heptane or cycloalkane, such as cyclohexane or a mixture thereof, or an aromatic hydrocarbon such as toluene, or a chlorinated hydrocarbon, as a water-immiscible aprotic solvent. such as dichloromethane. The process according to claim 1, wherein the molar ratio of the phase transfer catalyst to 3-phenoxybenzaldehyde is from 1: 5 to 1:50. The process according to claims 1-2, wherein the starting molar ratio of the amount of water to the total amount in water of soluble cyanide is greater than 0.05.