Redefining the Coordination Mode of 1,2,4-Triazolylidene: Bridging the Gap Between Molecular Organometallic Chemistry...

Although molecular organometallic complexes are widely exercised across various chemistry domains, their evolution into extended porous frameworks has been lacking for C-donor NHC ligands. In this study, we present the first such example by leveraging the rare coordination of the 1,2,4-triazolylidene N2 site, embedded within a bis(NHC) ligand scaffold (L1), in conjunction with flexible coordination mode of the Cu^I-ion. Initially, the formation of discrete multinuclear Cu^I-NHC complexes (2a,b) was observed, as confirmed by extensive NMR analyses, which transformed into highly crystalline and porous extended framework (3b) upon crystallization, marking the first report wherein the M─C_NHC bonds play critical roles in governing the framework topology. The structural integrity and origin of stability was thoroughly investigated using a combination of detailed analytical and theoretical studies.