SYNTHESES AND CHARACTERIZATION OF DINUCLEAR GOLD(I) RING AND OPEN-RING COMPLEXES CONTAINING SATURATED AND UNSATURATED DITHIOL BRIDGING LIGANDS AND PHOSPHINE OR BIS(DIPHOSPHINE) DONOR LIGANDS - CRYSTAL-STRUCTURES OF [AU2(MU-S(CH2)3S)(MU-DPPM)],[AU2(MU-MNT)(PPH3)2], [AU2(MU-S2C6H4)(PPH3)2], AND [AU4(MU-S2C6H3CH3)2(PET3)2]

Dinuclear gold(I) complexes of the type [Au2(mu-dithiolate)(L)n] where L is a phosphine or bis(dialkylphosphine) have been synthesized. The molecular structures of )(mu-dppm)][dppm=bis((diphenylphosphino)-metha ne)] (1), [Au2(mu-MNT)(PPh3)2] (MNT = 1,2-dicyanoethene-1,2-dithiolate -S,S') (2), and [Au2(mu-S2C6H4)-(PPh3)2] (3) are described. In additio n, the structure of the tetranuclear bis(dithiolate) [Au4(mu-S2C6H3CH3 )2(PEt3)2] (4) is reported. Compound 1 exhibits linear S-Au-P coordina tion and significant metal-metal interaction, Au ... Au = 3.128(1) ang strom. The open-ring complexes 2 and 3 contain an irregular three-coor dinate gold(I) center and a ''normal'' two-coordinate, linear gold(I) center in contrast to 1. Compound 4 is a result of [Au(PEt3)]+ coordin ation to [Au2(mu-S2C6H3CH3)2]2-. Pertinent crystal data are as follows : Compound 1 crystallized in the monoclinic space group C2/c with a = 29.765(9) angstrom, b = 11.479(2) angstrom, c = 18.032(4) angstrom, be ta = 114.65(1)-degrees, and V = 5600(2) angstrom3. Compound 2-Et2O cry stallized in the space group P2(1)/c with a = 17.663(5) angstrom, b = 14.185(3) angstrom, c = 18.780(3) angstrom, beta = 114.853(18)-degrees , and V= 4269(2) angstrom3. Compound 3 crystallized in the space group P2(1) with a = 10.761(4) angstrom, b = 10.687(4) angstrom, c = 16.227 (5) angstrom, beta = 98.82(3)-degrees, and V = 1844(1) angstrom3. Comp ound 4 crystallized in the space group P2(1) with a = 9.767(2) angstro m, b = 12.373(3) angstrom, c = 14.096(3) angstrom, beta = 92.71(2)-deg rees, and V = 1707(1) angstrom3.