Gold(I) Compounds without Significant Aurophilic Intermolecular Interactions: Synthesis, Structure, and Electronic Properties of Ph3PAuC(O)NHMe and Au3(PhCH2NCOMe)3: Comparative Monomeric and Trimeric Analogues of the Solvoluminescent Trimer, Au3(MeNCOMe)3

Abstract

The preparations of Ph(3)PAuC(O)NHMe( )()and Au(3)(PhCH(2)N=COMe)(3) are reported. In solution Ph(3)PAuC(O)NHMe is unstable and readily deposits metallic gold. Colorless needles of the monomeric complex, Ph(3)PAuC(O)NHMe, crystallize in the monoclinic space group P2(1)/c, with a = 8.993(2) Å, b = 22.583(5) Å, c = 8.932(2) Å, beta = 98.22(2) degrees, at 123 K with Z = 4. Refinement of 2609 reflections and 114 parameters yielded R = 0.0455. A hydrogen-bonded intermolecular network links molecular units through N-H.O hydrogen bonds. No aurophilic interactions are present in this solid. The crystal structure of the cyclic trinuclear organogold compound, Au(3)(PhCH(2)N=COMe)(3), reveals that the complex does not associate into a trigonal prismatic array via intermolecular interactions of gold(I) centers as is seen in the triangular complex, Au(3)(MeN=COMe)(3). Rather, the complex packs in a stair-step fashion with eight discrete molecules in the asymmetric unit. Additionally, the solvent-stimulated emission (solvoluminescence) associated with Au(3)(MeN=COMe)(3) is not observed for this complex. Colorless needles of Au(3)(PhCH(2)N=COMe)(3) crystallize in the monoclinic space group P2(1), with a = 17.311(6) Å, b = 34.761(10) Å, c = 18.052(6) Å, beta = 94.73(2) degrees, at 133 K with Z = 16. Refinement of 16 250 reflections and 985 parameters yielded R = 0.0735.