Condensed thiophenes from sulfur bridging. I. Phenanthro[4,5‐<i>bcd</i>]thiophene

Abstract

Abstract Treatment of phenanthrene with hydrogen sulfide and an alumina catalyst at 630° gives phenthro[4,5‐ bcd ]thiophene (XVII). Spectral properties of XVII, its sulfoxide, and its sulfone are presented. Other examples of the direct insertion of a sulfur bridging atom into an aromatic molecule are reviewed.