Heterochiral Self-Discrimination Driven Dimerization of Polynuclear Gold(I)-Sulfido Complexes with Enhanced Phosphorescence

Abstract

Decanuclear chiral gold(I) sulfido clusters (SSDP-Au10 and RSDP-Au10) have been assembled by taking advantage of the judiciously selected SDP ligands (SDP = 7,7’-bis(diphenylphosphino)-1,1’-spirobiindane). Interestingly, an achiral heterodimer icosanuclear meso-cluster (mesoSDP-Au20) has been obtained by simply mixing SSDP-Au10 and RSDP-Au10 in a 1:1 ratio. These gold(I) complexes have been found to display intense near-infrared (NIR) luminescence with an emission maximum at around 750 nm in the solid state. The photoluminescence quantum yield (PLQY) of mesoSDP-Au20 in drop-cast solid-state thin film has been found to show a significant enhancement from 8% in the SSDP-Au10 and RSDP-Au10 to 25%. In addition, the dimerization process with heterochiral self-discrimination has been found to be sensitive to the solvent polarity and configuration of the diphosphine ligand. This work has provided a platform for the investigation and mechanistic understanding of heterochiral self-sorting and assembly processes.