PROCESS FOR DEHYDROHALOGENIZATION OF 7-HALO-OR 1,7-DIHALO -DIHYDROCEDEINONE DIALKYLKETALS

摘要

A process for the dehydrohalogenation of a 7-halo- or a 1,7-dihalodihydrocodeinone dialkyl ketal of the general formula (I): IMAGE (I) in which R represents an alkyl group containing from 1 to 6 carbon atoms, X represents hydrogen or chlorine or bromine and Y represents chlorine or bromine which comprises subjecting the ketal to the action of a base in the presence of a polar aprotic solvent. The process has utility in facilitating the production of codeine.