Nucleophilic substitution of 3-fluorosulfonyloxy cephalosporins with organocuprates
作者:Gregory P. Roth、Scott A. Peterson、Joydeep Kant
DOI:10.1016/s0040-4039(00)79294-x
日期:1993.11
3-Fluorosulfonyloxy cephems readily undergo addition-elimination reactions with organocuprates derived from the corresponding Grignard reagents. This chemistry presents an efficient, cost effective process for the preparation of 3-substituted cephems.
Reductive Cross-Coupling of 3-Substituted Δ<sup>3</sup>-Cephems with Alkenyl Halides in an Al/PbBr<sub>2</sub>/NiBr<sub>2</sub>(bpy) Triplemetal Redox System. Synthesis of 3-Alkenyl-Δ<sup>3</sup>-cephems
作者:Hideo Tanaka、Jinfeng Zhao、Hiroshi Kumase
DOI:10.1021/jo001429b
日期:2001.1.1
successfully by cross-coupling 3-(trifluoromethylsulfonyloxy or chloro)-delta 3-cephem with alkenylhalides, e.g., vinyl bromide, trans-1-bromo-1-propene, and trans-beta-bromostyrene in an Al/cat.PbBr2/cat.NiBr2(bpy)/NMP (or DMF) system. Reduction of 3-(trifluoromethylsulfonyloxy)-delta 3-cephem into norcephalosporin was also achieved by a similar reaction in the presence of 5 molar equiv of water. Scope