SYNTHESIS OF CYANOCARBOXYLIC ACID ALKYL ESTERS

摘要

Provided is a process for obtaining a compound of formula (I): N≡C-CH₂-A-C(O)-OR, wherein Hal is halogen selected from F, Cl, Br or I, A denotes a bond or a divalent spacer selected from alkylene and arylene groups, and R is a C_1-4 alkyl group, by reacting a compound of formula (II): Hal-CH₂-A-C(O)-OR, wherein Hal is a halogen atom selected from F, Cl, Br and I, and wherein A and R are as defined above, with hydrogen cyanide in the presence of a first base, wherein the molar ratio between hydrogen cyanide and said first base is from 1:0.3 to 1:0.95 and the molar ratio between hydrogen cyanide to the compound of formula (II) is at least 1:1.