Copper Catalyzed Reactions of Penicillin Derivatives With t-Butyl Perbenzoate

Abstract

The benzoyloxylation of penicillin derivatives at C5, on treatment with t-butyl perbenzoate in the presence of a copper catalyst, is facilitated by a phthalimido group at C6 when the substituents on the lactam ring are in the cis orientation, but hindered when the groups are trans substituted. In the absence of a C6 substituent, a competing reaction occurs in which the thiazolidine ring is cleaved.