Construction of cephem framework via sequential reductive 1,2-elimination–hydride addition in a tributyltin hydride–copper(I) chloride–NMP system: synthesis of 3-norcephalosporin
Abstract
A sequential reductive 1,2-elimination and hydride addition process for 3,4-disubstituted butenoates derived from penicillin is successfully performed with the aid of a combination of tributyltin hydride and copper(I) chloride in N-methyl-2-pyrrolidinone (NMP) to afford 3-norcephalosporin.