ABSTRACT
This study characterizes a new polymorph of the title compound, [CuCl(C18H15P)3], and analyses the influence of the extensive network of weak hydrogen-bonding interactions in the generation of this different crystal structure. The compound crystallizes in the centrosymmetric space group C2/c with two crystallographically independent molecules per asymmetric unit, in contrast with the previously determined polymorph which crystallizes in the noncentrosymmetric space group P3 with three crystallographically independent molecules in the asymmetric unit, each with crystallographically imposed C3 symmetry [Gill, Mayerle, Welcker, Lewis, Ucko, Barton, Stowens & Lippard (1976). Inorg. Chem. 15, 1155-1168]. The geometries of the two molecules of the title compound are very similar, with each having an approximately tetrahedral coordination around the central Cu atom and approximate C(s) molecular symmetry. The molecules pack in chains parallel to the crystallographic b axis, connected by C-H...Cl and C-H...pi(phenyl) hydrogen bonds.
ABSTRACT
In the title complex, [Au(C(12)H(8)N(5)O(4))(C(18)H(15)P)], the coordination geometry about the Au(I) ion is linear, with one deprotonated 1,3-bis(4-nitrophenyl)triazenide ion, [O(2)NC(6)H(4)N=N-NC(6)H(4)NO(2)](-), acting as a monodentate ligand (two-electron donor), and one neutral triphenylphosphine molecule completing the metal coordination. The triazenide ligand is almost planar (r.m.s. deviation = 0.0767 A), with the largest interplanar angle being 11.6 (7) degrees between the phenyl ring of one of the terminal 4-nitrophenyl substituents and the plane defined by the N=N-N triad. The Au-N and Au-P distances are 2.108 (5) and 2.2524 (13) A, respectively. Pairs of molecules generated by centrosymmetry are associated into a supramolecular array via intermolecular C-H...O interactions, and N...C and N...O pi-pi interactions.
