Isomerization of 3<i>H</i>‐ to 2<i>H</i>‐[1]Benzothieno[3,2‐<i>b</i>]pyrroles and Synthesis of the First Merocyanine Dyes Based on Them

Abstract

Abstract New 2 H ‐[1]benzothieno[3,2‐ b ]pyrroles were synthesized by a [1,5]‐sigmatropic shift of 3 H ‐benzothienopyrroles. The dependence of the rearrangement on solvent and temperature was studied. The first merocyanine dyes based on both 3 H ‐ and 2 H ‐benzothienopyrroles were synthesized and characterized by NMR‐ and UV/Vis spectroscopy, mass spectrometry, and X‐ray crystallography.(© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2006)