Synthesis of 3-alkenyl-Delta(2)-cephems by copper(I) chloride-promoted alkenylation of 3-trifluoromethylsulfonyloxy-Delta 3-cephem with alkenyltributyltins
Synthesis of 3-alkenyl-Delta(2)-cephems 3 was performed in regioselective manner by copper(I) chloride-promoted alkenylation of 3-trifluoromethylsulfonyloxy-Delta(3)-cephem 1 with alkenyltributyltins. Subsequent Diels-Alder reaction of the 3-vinyl-Delta(2)-cephem 3a with acrolein opened a new access to C(2)-C(3) fused tricyclic cephalosporin 9. Copyright (C) 1996 Elsevier Science Ltd