Heteroaryl iminothioindoxyl (HA-ITI) photoswitches <i>via</i> regioselective aza-Wittig synthesis: unifying red-shifted absorption, large <i>E</i>/<i>Z</i> band separation, and tunable thermal recovery.

ABSTRACT: Herein we introduce heteroaryl-substituted iminothioindoxyl (HA-ITI) photoswitches featuring N-heterocyclic moieties based on indole or benzimidazole. A regioselective aza-Wittig reaction of thioisatin, previously unexplored for the synthesis of imino-based photoswitches, enabled the obtention of HA-ITI derivatives and provides an alternative and versatile synthetic access to similar analogues. HA-ITIs undergo blue light-induced Z → E photoisomerization, followed by very fast thermal E → Z back isomerization at room temperature (µs to ms timescale; resolved by transient absorption spectroscopy). Irradiation at low temperature (<200 K) provided clear proof for the reversible T-type switching of HA-ITI. This behavior was corroborated by the changes in the U

SUBMITTER: Chen-Wu J 

PROVIDER: S-EPMC12729054 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature