New heterocyclic systems to afford microsecond green-light isomerisable azo dyes and their use as fast molecular photochromic switches†
Abstract
The use of benzothiazole as an electron-withdrawing group allows obtaining the fastest thermal isomerisation kinetics reported heretofore for neutral azo dyes (70 μs at 298 K). These green light activatable molecules are valuable candidates as molecular photoswitches since they tolerate thousands of working cycles with no sign of fatigue.