Uniform Half‐substituted Chiral Arylcycloparaphenylene: Synthesis, Crystal Structure, and Chiroptical Properties

The strategic implementation of aryl-functionalization in every phenyl group in organic architectures presents a transformative approach to constructing novel molecular nanocarbon materials. In this present work, we demonstrate the first synthesis of a uniform and chiral half-aryl substituted cycloparaphenylene (CPP), [6]CPP-12tBuPh. Single-crystal X-ray diffraction analysis unambiguously confirms its hoop-shaped structure and the existence of planar chirality arising from stereochemically distinct substituent orientations. The resolved pS and pR enantiomers display mirror-imaged circular dichroism (CD) signals and a high luminescence dissymmetry factor (|glum| = 2.6 × 10-2). Photophysical characterization reveals the emergence of aggregation-induced emission (AIE) behavior, with pure [6]CPP-12tBuPh powder sample exhibiting intense orange fluorescence.