Optical resolution via chiral auxiliaries of curved subphthalocyanine aromatics

Abstract

Chiral conjugated materials with curved topologies hold significant promise for advanced optoelectronic applications. Among these, bowl-shaped subphthalocyanine (SubPc) aromatics are particularly noteworthy due to their superb optoelectronic properties and synthetic versatility. Despite their potential, the development and application of inherently chiral SubPcs as functional materials have been hampered by the scalability and feasibility limitations of current high-performance liquid chromatography methods. In this work, we employ axial derivatization with BINOL-based chiral auxiliaries to achieve the optical resolution of C₃-symmetric SubPcs. This approach allows us to obtain optically active meta and ortho-substituted SubPc derivatives in high yields and enantiomeric excess through straightforward organic chemistry protocols. In addition, we serendipitously observe unprecedented bowl-to-bowl inversion of the SubPc macrocycle upon removal of the derivatizing ligand under specific experimental conditions. These findings represent a significant milestone in the study of chirality in curved aromatics.