Chiral bowl-shaped thiazole-embedded B(iii)-azatriphyrins(2.1.1): a nonaromatic platform via triple core-modification

Abstract

We report the synthesis of a novel class of thiazole-embedded B(III)-monoazatriphyrin(2.1.1) macrocycles through a stepwise strategy that combines meso-nitrogen insertion, pyrrole-to-thiazole replacement, and an ortho-phenylene/naphthylene C₂ meso-bridge. These macrocycles are nonaromatic and adopt chiral, bowl-shaped geometries that form stable enantiomers exhibiting distinct circular dichroism signals. Their optical spectra show a blue-shifted high-energy absorption band and a red-shifted lower-energy absorption band, while electrochemical studies reveal tunable redox properties. This work provides a versatile strategy for constructing core-modified, contracted porphyrinoids as a promising platform for chiral NIR-active dyes.