Reaction Of α-amido Sulfones With Functionalized Nitrocompounds: A New Two-step Synthesis Of N-alkoxycarbonyl-2,5-disubstituted Pyrroles

Reaction of α-amido sulfones with nitro ketals promoted by KF on alumina provides the corresponding adducts which, upon treatment with p-toluenesulfonic acid, generate the corresponding N-alkoxycarbonyl-2,5-disubstituted pyrroles. The latter transformation involves a cascade process including ketal cleavage, ring closure and final aromatization by nitrous acid elimination.