THE PREPARATION OF PYRROLE-2-CARBOXYLATES FROM VINYL SULFONES

The reaction of the anion of ethyl isocyanoacetate with suitably substituted vinyl p-tolyl sulfones gives fair to good yields of pyrrole-2-carboxylates substituted in the 3-, 4- or 3- and 4-positions. From the reaction of 1-phenyl-1-tolylsulfonylethene with ethyl isocyanoacetate, two diastereoisomers of ethyl 4,6-diphenyl-4,6-bis(p-tolylsulfonyl)-3,4,5,6-tetrahydro-2H-azepine-2-carboxylate (4) were also isolated.