Process for the preparation of acyl cyanide compounds

Claim 1

Process for the preparation of acyl cyanide ##STR12## wherein R is alkyl or substituted alkyl with 1 to 8 carbon atoms, wherein the substituents are selected from alkoxy or carbalkoxy of up to 4 carbon atoms in the alkoxy moiety, nitro, nitrile and halo; cyano-carbonyl substituted alkyl; cycloalkyl or substituted cycloalkyl with 3 to 12 carbon atoms wherein the substituent is selected from alkyl, alkoxy and carbalkoxy of up to 4 carbon atoms in each alkyl moiety, nitro, nitrile and halo; aryl or substituted aryl wherein the substitutents are selected from alkyl, alkoxy and carbalkoxy of up to 4 carbon atoms in the alkyl moiety, nitro and halo; or represents an optionally substituted 5-membered or 6-membered heterocyclic radical which can additionally also be fused with a benzene ring, wherein said substituents are selected from alkyl, alkoxy and carbalkoxy of up to 4 carbon atoms in each alkyl moiety, nitro, nitrile and halo; which process comprises reacting an acid halide of the formula ##STR13## wherein R' is alkyl or substituted alkyl with 1 to 8 carbon atoms, wherein the substituents are selected from alkoxy or carbalkoxy of up to 4 carbon atoms in the alkoxy moiety, nitro, nitrile and halo; or ##STR14## substituted alkyl; cycloalkyl or substituted cycloalkyl with 3 to 12 carbon atoms wherein the substituent is selected from alkyl, alkoxy and carbalkoxy of up to 4 carbon atoms in each alkyl moiety, nitro, nitrile and halo; aryl or substituted aryl wherein the substituents are selected from alkyl, alkoxy and carbalkoxy of up to 4 carbon atoms in the alkyl moiety, nitro and halo; or represents an optionally substituted 5-membered or 6-membered heterocyclic radical which can additionally also be fused with a benzene ring, and X is halogen, with an alkali metal cyanide or anhydrous hydrocyanic acid in the presence of a heavy metal cyanide, at a temperature of between 100° C. and 300° C.