The n-acidic coinage-metal cyclic trinuclear complexes with Lewis or n-bases and the relevant applications

Coinage-metal cyclic trinuclear complexes (CTCs) with azolate ligand equipped with strong electronwithdrawing substituents (e.g., CF3, NO2) represent the underlying members in the CTC family. The rapid developments of these strong n-acidic CTCs have led to a series of applications, including but not limited to chemical sensing towards aromatic volatile organic compounds (VOCs), adsorptive desulfurization, giving birth to new coordination compounds or metal nanoclusters with intriguing emissive behaviours, catalytic organic reactions. Most of these applications are related to the reactions of strong n-acidic CTCs with Lewis/n-bases, involving the cooperative effect of Lewis acidity and strong n-acidity of these CTCs. This review mainly focuses on the applications and reactions of strong n-acidic CTCs which were reported in the recent decade, and discusses their relationship with the previous reports. We aim to share the beauty and unique values of strong n-acidic CTCs with world-wide researchers, so that the considerable developments of the materials with cyclic trinuclear units (CTUs) can be expected, for better meeting the multiple real-world requirements of human.