PROCESS FOR PREPARING SUBSTITUTED P-CHLOROPHENYL ALIPHATIC NITRILES

Abstract: 3-Methyl-2-p-chlorophenyl butyrylnitrile is useful as an intermediate for preparing the (±)-cyano(3-phenoxy­ phenyl)methyl ester of (±)-3-methyl-2-(4-chlorophenyl) butanoic acid which is useful as an insecticide and acaricide.

Description: PROCESS FOR PREPARING 3-ALXn-2-p-CHLOROPHEP¯INL BUTYRYLNITRILE Background of the Invention 3-Methyl-2-p-chlorophenyl butyrylnitrile is useful as an intermediate for preparing the (+)-cyano(3-phenoxyphenyl)methyl ester of (+)-3-methyl- 2-(4-chlorophenyl)butanoic acid which is useful as an insecticide and acaricide composition and has the chemical structure EMI1.1 This compound can be prepared by reacting 3-methyl-2-pchlorophenyl butyryl acid chloride with m-phenoxybenzaldehyde cyanohydrin in the presence of an acid scavenger such as triethylamxne. 3-Methyl-2-p-chlorophenyl butyryl acid chloride can be prepared from 3-methyl-2-p-chlorophenyl butyrylnitrile by hydrolyzing the nitrile to an acid and converting the acid to an acid chloride by standard known procedures. Detailed Description of the Invention 3-Alkyl-2-p-chlorophenyl butyrylnitrile can be prepared by reacting p-chlorophenyl acetylnitrile with a lower alkyl sulfonate of a lower alkyl alcohol under phase transfer catalytic conditions in the presence of a 40 weight percent to saturated basic solution such as 50% NaOH or 50% KOH. Any number of phase transfer catalysts can be used such as tetrabutylphosphonium chloride, benzyltriethylammonium chloride, tricaprylmethylammonium chloride, tetrabutylammonium chloride, or cryptates or crown ethers such as 18-crown-6. The amount of phase transfer catalyst present can range from 1/2 to 10 weight percent. The reaction can be conducted at a temperature from about OOC to about 2000C, preferably from about 500C to- about 100 OC. Reaction times are from one-half hour to 48 hours, preferably two to three hours depending on reaction temperature. The reaction rate depends upon reaction temperature. The reaction is as follows: EMI3.1 <tb> <SEP> O <SEP> 50% <SEP> Caustic <SEP> (NaOH) <tb> C1 <SEP> < <SEP> 2CN <SEP> + <SEP> ROssR' <SEP> Phase <SEP> Transfer <tb> <SEP> O <SEP> O <SEP> Catalyst <tb> <SEP> C1 <SEP> - <SEP> CER <SEP> + <SEP> R'S03 <tb> <SEP> CN <tb> wherein R can be C1-C5 primary or secondary alkyl such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, valeryl and isovaleryl and R' can be primary, secondary or tertiary C1-C5 such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, valeryl, isovaleryl or t-valeryl. The above process has an additional advantage in that the alkyl sulfonate of the alkyl alcohol are high boiling (yv2000C) and do not require pressure equipment during the reaction as do lower alkyl chlorides (RC1 wherein R is as defined above) whose boiling point is about 350C. The process of this invention is exemplified by the following example. EXAMPLE I 3-METHYL-2-p-CHLOROPHENYL BUTYRYLNITRILE In a one liter flask was placed 135 grams (g) (0.9 mole (m)) of p-chlorophenyl acetonitrile and 138 g (1 m) of isopropyl methanesulfonate. To this was added in one portion 300 milliliters (ml) of 50% NaOH and 30 ml of 40% tetrabutylammonium hydroxide. The mixture was heated on a steam bath with vigorous stirring for three hours. Two liters of water was then added and the mixture extracted three times with 200 ml portions of CH2Cl2. The organic layers were combined, dried with MgS04 and evaporated. A quantitative yield of 3-methyl 2-p-chlorophenyl butyrylnitrile was obtained. The product was identified by infrared and nuclear magnetic resonance spectra as the title compound having the structural formula EMI4.1

Claims: WT IS CLAIMED: 1. A process for preparing a 3-alkyl-2-p c;hlorophenyl butyrylnitrile having the formula EMI5.1 therein R is a C1-C5 primary or secondary lower alkyl elected from the group consisting of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, valeryl and isovaleryl comprising reacting p-chlorophenyl acetyl- rile with a lower alkyl sulfonate of a lower alkyl icchol having the formula EMI5.2 A derein R is a C1-C5 primary or secondary lower alkyl selected from the group consisting of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, valeryl and isovaleryl and Rl is a C1-C5 lower alkyl selected from the group consisting of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, valeryl, isovaleryl or t-valeryl in the presence of a base and a phase transfer catalyst. 2. The process of Claim 1 wherein R is isopropyl. 3. The process of Claims 1 or 2 wherein the base is selected from the group consisting of 50% NaOH and 50% KOH, the reaction temperature is from about OOC to about 2000C and the phase transfer catalyst is selected from the group consisting of tetrabutylphosphonium chloride, benzyltriethylammonium chloride tricaprylmethylammonium chloride or tetrabutylammonium chloride.

Inventors: FELIX, RAYMOND ANTHONY
Applicants: STAUFFER CHEMICAL COMPANY
Application year: 1981
Main classification: C07C121
IPC codes: C07C67, C07C253, B01J31, C07C255, C07B61