Sulfur-free penicillin derivatives. VII. Multiple functionalization of 2-azetidinyl-3-methyl-2-butenoates
作者:Saul Wolfe、Chia-Cheng Shaw
DOI:10.1139/v82-025
日期:1982.1.15
in the 3′-position of the azetidinone ring, have been converted to bis-allylic formates via bromination of both methyl groups with excess N-bromosuccinimide, and displacement of both bromines by formate ions in methylene chloride solvent. The diformates react smoothly with a deficit of a boron halide to form E/Z mixtures of halogeno-formates, in which the E-isomer predominates. Depending on the 3′-azetidinyl