An improved synthesis of pyrroles from <i>N‐p</i>‐toluenesulfonylglycine esters and α,β‐unsaturated aldehydes and ketones

Abstract

Abstract N‐p ‐Toluenesulfonylglycine esters 2 condensed with α,β ‐unsaturated carbonyl compounds 1 in the presence of the non‐nucleophilic base DBU to give hydroxypyrrolidines 3 . Dehydration with phosphorus oxychloride‐pyridine, followed by DBU mediated elimination of p ‐toluenesulfinic acid, gave a series of synthetically useful pyrrole‐2‐carboxylates 5 .