Synthesis of spiropyrans and merocyanine dyes based on 1-benzothieno [3, 2-b] pyrrole

…, VZ Shirinian, AK Mailyan, MM Krayushkin

Index: Shimkin; Shirinian; Mailyan; Krayushkin Russian Chemical Bulletin, 2009 , vol. 58, # 2 p. 380 - 386

Full Text: HTML

Citation Number: 3

Abstract

A convenient method was developed for the synthesis of photochromic spiropyrans and merocyanine dyes of the 1-benzothieno [3, 2-b] pyrroline series based on the conventional condensation of the analog of Fischer's salt, viz., 1, 2, 3, 3-tetramethyl-3 H-[1] benzothieno- [3, 2-b] pyrrolium triflate, with aromatic 2-hydroxyaldehydes. Unlike Fischer's salt, benzothieno-pyrrolium salts readily undergo the [1, 5]-sigmatropic rearrangement giving ...