Dinuclear Gold(I) Chloride Complexes with Diarsine Ligands

Recently, we have developed synthetic methods for preparing diarsenic ligands. Herein, dinuclear gold(I) chloride complexes with various kinds of diarsenic ligands [Au2Cl2(diars)] were synthesized (diars = dpae, dpap, dpab, cis-dpav, trans-dpav, dpapz, and dpaq). X-ray crystallography revealed that they can form intra- or intermolecular aurophilic interactions depending on the ligand structure except for dpab. Crystal polymorphs of Au2Cl2(dpae) and Au2Cl2(dpap) were observed because of the flexible alkylene linkers of the diarsine ligand. The emission behaviors of the complexes were drastically changed by the ligands, which should affect the energy barrier for internal conversion from the intraligand excitation state to the halide-to-ligand charge transfer one. Some of the complexes accordingly showed luminescent mechanochromism and/or thermochromism.

Automated summary

By synthesizing dinuclear gold(I) chloride complexes with various kinds of diarsenic ligands, it was found that they can form intra- or intermolecular aurophilic interactions depending on the ligand structure. Some of the complexes showed luminescent mechanochromism and/or thermochromism, indicating a change in emission behaviors affected by the ligands.