Chiral Copper(I) Halide Clusters and Coordination Chain Exhibiting Photoluminescence and Circularly Polarized Luminescence

The synthesis of chiral atomically precise metal clusters is hindered by the challenge of achieving desirable crystallinity, and the investigation of chiral alkynyl copper(I) halide compounds with circularly polarized luminescence (CPL) responses remains a relatively unexplored area. In this study, we successfully synthesized five gram-scale pairs of enantiomers by utilizing chiral proparylbenzylamine ligands and copper halides as precursors. Notably, these enantiomers incorporate ionic, coordinate bonds, and C–H···π interactions to significantly enhance their stability and crystallinity. Derived from either Br– or I–, the enantiomers exhibited distinct skeletal characteristics, resulting in four different structural types. A thorough analysis was undertaken to elucidate the origins of the chirality within each of these structural motifs. Remarkably, all of the enantiomers displayed photoluminescence and mirror-image circular dichroism (CD) responses. Of particular interest, the one-dimensional (1D) compound R/S-1 exhibited pronounced CPL activities and an anisotropy factor (glum) of ∼0.007 in its crystalline state. This investigation contributes to the understanding of structure–property relationships in chiral compounds and offers a new strategy for designing materials with targeted functionalities.