Synthesis of trans(±)6-phenoxyacetamido-1-methylene-3,3-dicarboxymethyl-1-carbapenam

Methyl 4-benzylidene-2-pyrroline-2-carboxylate and dimethyl-4-methylene-5-pyrroline-2,2-dicarboxylate were prepared by N-chlorination – dehydrochlorination starting from the corresponding 4-alkylidene- or 4-arylidene-pyrrolidine. Structure of the pyrroline compound was determined by spectrometry and by reaction with α-azidoacetyl chloride. The 2-carbomethoxy-4-benzylidene-Δ 2 -pyrroline compound gave, on reaction with α-azidoacetyl chloride, 2-benzylidene-5-carbomethoxy-6-azido-1-carbapenam. In the case of the 2,2-dicarbomethoxy-4-methylene-Δ 5 -pyrroline, trans-1-methylene-3,3-dicarbomethoxy-6-azido-1-carbapenam was formed. When N-chlorination – dehydrochlorination was carried out on 2-carbomethoxy-4-methylenepyrrolidine, double bond isomerization occurred with formation of 2-carbomethoxy-4-methylpyrrole.