Cleavage of the N(1)C(4) bond of 4-(4′-hydroxyphenyl)-azetidine-2-ones via quinone methide intermediates

In this paper we describe a novel ring-opening reaction in which 4-(4′-hydroxyphenyl)-azetidine-2-ones, on treatment with base, rearrange to quinone methide intermediates with concomitant cleavage of the C(4)N(1) bond. The quinone methide intermediate serves as a substrate for Michael-type 1,6 conjugate additions.