Diagnostic Absolute Configuration Determination of Tetraphenylethene Core-Based Chiral Aggregation-Induced Emission Compounds: Particular Fingerprint Bands in Comprehensive Chiroptical Spectroscopy

Tetraphenylethylene (TPE) and its derivatives are the typical aggregation-induced emission (AIE) compounds with helical chirality, and they have enormous applications potential in chiral sensor, asymmetric catalyst, optoelectronic materials, and so on. The aggregation-induced helical chirality of TPE and its derivatives can only be observed in condensed phase such as crystalline or film state. The accurate determination of absolute configuration (AC) of TPE core compounds is complicated and difficult, especially when there is no heavy atoms exist in their structures. Herein, we demonstrate a powerful and convenient method to quickly determine the helical chirality of these stereochemically labile TPE core compounds through the combination of comprehensive solid-state chiroptical spectroscopy and theoretical calculation. Our study reveals that from lower to higher energy of the fingerprint region, the first electronic circular dichroism (ECD) band in the 300–450 nm or the first most intensive vibrational c...