NHC–Au(i) complexes bearing trispyrazolyl borate (Tp) ligands: efficient platforms for bimetallic species

Abstract

Treatment of NHC–AuCl (NHC = IPr and IMes) complexes with equimolar amounts of KTp^R2 (R = Me, H) salts in tetrahydrofuran produces in high yields the heteroleptic complexes 3–6 with the general formula NHC–Au–Tp^R2. As the Tp^R ligand in complexes 3–6 features a k¹-N type coordination toward the gold(I) center, the subsequent addition of group 10 and 11 metal precursors (Ni^II, Pt^II, Cu^II) results in the isolation of heterobimetallic Au/M complexes supported by Tp^R platforms. All new metal complexes have been fully characterized by elemental analysis and NMR spectroscopy, and in the case of 3, 4 and 6 by X-ray crystallography.