Benchtop synthesis and crystal structure determination of a monomeric N-heterocyclic carbene complex of copper(I) chloride

(1,3-Bis(2,4,6-trimethylphenyl)imidazol-2-ylidene) copper(I) chloride (1) was prepared by the reaction of 1,3-bis(2,4,6-trimethylphenyl)imidazolium chloride and cop-per(I) oxide in refluxing tetrahydrofuran. In contrast to previously published methods of preparation of N-hetero-cyclic carbene complexes of copper(I) halides, this synthesis requires neither an inert atmosphere nor scrupulously dry solvents. The structure of 1 was determined by elemental analysis, ¹H and ¹³C NMR, and a single-crystal X-ray diffraction study. The X-ray crystal data reveal linear coordination about the copper(I) center and linear chains of molecules formed with intermolecular head-to-tail C-H⋯Cl interactions.