Generation and Reaction of Copper(I) Hydride in Copper(I) Chloride/Tributyltin Hydride/NMP System: Synthesis of 3-Norcephalosporin

Tanaka, H.; Yamaguchi, Y.; Sumida, S.-i.; Kuroboshi, M.; Mochizuki, M.; Torii, S. J. Chem. Soc., Prkin Trans. 1. 1999, 3463.

Synthesis of 3-norcephalosporin I (R1 = NHCOCH2Ph, R2 = CH2C6H4OMe-p) was performed successfully by reaction of either 3-trifluoromethylsulfonyloxy-D3-cephem II (Tf = SO2CF3), allenecarboxylate III or 3,4-disubstituted but-2-enoates IV (X = Cl, OTf, OTs) with copper(I) chloride and tributyltin hydride in N-methylpyrrolidin-2-one (NMP). Generation and reactions of a copper(I) hydride species in the copper(I) chloride-tributyltin hydride-NMP or N,N-dimethylformamide (DMF) system are discussed.