Bisarylindenols: fixation of conformation leads to exceptional properties of photochromism based on 6π-electrocyclization†
Abstract
Thermally irreversible photochromic 1-tert-butyl-substituted 2,3-bisthiazolylindenol has been synthesized. It showed perfect diastereoselectivity and high ring-closing quantum yield with high conversion ratio to the closed form. The collaborative interaction of two intramolecular hydrogen bonds and the steric restriction fixed the conformation in favour of