Synthesis of oxidized thienopyrroles using HOF·CH3CN.

An efficient transformation of the sulfur atoms to the sulfonyl group in a range of thienopyrroles was achieved by using the HOF·CH(3)CN complex. Mild conditions, high yields, and easy purification are the main features of this novel route. Most new materials exhibit considerable red-shift absorptions in the UV/visible range relative to the parent compounds.