PROCESS FOR PRODUCING PHTHALIDE

摘要

The present invention is concerned with a process for the hydrogenolysis of 3-chlorophthalide wherein the formation of undesired by-products is substantially decreased and yields of phthalide of over 90% are obtained. This process which is carried out in the presence of a precious metal catalyst is characterized in that 3-chlorophthalide is subjected to hydrogenolysis in the absence of HCl-acceptors at a temperatures ranging between 50 and 250.degree.C, preferably between 80 and 130.degree.C.