Scope and Applicability of an Expedient Synthesis Leading to Polysubstituted 3‐(Carboxyphenyl)pyrroles

Abstract

A convenient three‐step route toward a functionalized pyrrole building block for novel anti‐inflammatory agents is reported. In contrast to previous strategies, the present approach focuses on inexpensive starting materials and application on a multigram scale. A high degree of functional diversity is demonstrated in various derivatives, and the scope and limitations of this route are discussed. Complementary to the described tetrasubstituted pyrroles, a novel ring‐closure protocol based on the Feist–Benary condensation affords trisubstituted analogues.

Keywords:

• chalkones
• Feist–Benary condensation
• Paal–Knorr cyclization
• pyrrole synthesis
• Stetter reaction