Abstract
A series of Au(I)–Cu(I) N-heterocyclic carbene (NHC) halide complexes [AuCu2(im(CH2py)2)2X]2+ where X = Cl (1), Br (2), I (3) was prepared by refluxing [AuCu2(im(CH2py)2)2(NCCH3)4]3+ with the appropriate halide in acetonitrile. The compounds were characterized by NMR, absorption, and fluorescence spectroscopy. They feature similar solution behavior and solid-state photoemissions. The solid-state structures feature a rhomboidal [AuCu2X]2+ core which is influenced by the type of halide. Compared to other Au(I)–Cu(I) NHC complexes, 1–3 comprise a new structural motif containing a bridging halide. The benzimidazolium analog of 1 was also characterized crystallographically. The structure of [AuCu2(benzim(CH2py)2)2Cl]2+(4) features different coordination modes of the NHC ligands with the carbenic carbon bonded to both gold and copper and the pyridyl groups bonded to the same copper(I) ion.
Disclosure statement
No potential conflict of interest was reported by the authors.