Gold(I) and Gold(III) complexes of the [CH(dppm)2]+ and C(dppm)2 PCP pincer ligand systems

Gold(III) complexes of the PCP pincer carbodiphosphorane (CDP) ligand C(dppm)(2) and gold(I) complexes of the conjugate CH acid [CH(dppm)(2)](+) were synthesized and characterized by single crystal diffraction and by NMR spectroscopy. The gold(I) complex [AuCl(CH(dppm)(2))-kappa P-2,P']Cl (1) exhibits an approximate trigonal planar AuClP2 core, whereas the gold center in the [Au(CH(dppm)(2))-kappa P-2,P')](TfO)(2) complex (2) is only two-coordinated (P(1)-Au(1)-P(4) around 167.3 degrees). Both complexes show no significant interaction between the gold(I) and the CDP carbon and consequently, an eight membered chelate ring is observed. [AuI(C(dppm)(2))-kappa P-3,C,P')](TfO)(2) (3) and [AuCl(C(dppm)(2))-kappa P-3,C,P')](NO3)(2) (4) were obtained via oxidation of complex 1 or 2 with iodine or nitric acid, respectively. The gold(III) center is stabilized in a square planar coordination geometry by two dppm units, the divalent carbon(0) atom of the C(dppm)(2) ligand system, and a halide ion. (C) 2017 Elsevier B.V. All rights reserved.