A novel method for the synthesis of 3,4-disubstitutedpyrrole-2,5-dicarboxylates from hydrazones derived from α-diazo esters

Hydrazones obtained from α-diazo esters were converted to pyrroles when heated with thionyl chloride in alcohol. Among hydrazones, those substituted with a benzene ring on the β-carbon to the ester are likely to give pyrroles in good yields.