Synthesis of tetraphenylethylene-based π-conjugated macrocycles and their chirality induction
摘要
Shape-persistent macrocycles with π-conjugated aromatic units represent a new class of macrocycles with abundant optical, electronic, and magnetic properties. However, the construction of dynamic chiral macrocycles from achiral building blocks remains largely unexplored. Herein, we present an efficient synthetic strategy involving quantitative and chemoselective acid-promoted alkyne benzannulations of the rationally designed achiral macrocyclic precursors. The resulting macrocycles possess electron-rich inner cavities, enhanced structural shape-persistence, and extended π-conjugation. These confined frameworks not only preserve aggregation-induced emission (AIE) characteristics but also display distinct size-dependent behavior, showing remarkable selectivity for encapsulating C70 over C60 fullerenes. Notably, the racemic macrocycles undergo efficient deracemization through chirality transfer from chiral solvents, yielding enantiomerically enriched optically active species. This study provides a rare demonstration of chiral solvent-induced deracemization in shape-persistent, π-conjugated macrocycles composed of achiral units, establishing new design principles for stimuli-responsive chiroptical materials.