2-COORDINATE AND 4-COORDINATE GOLD(I) COMPLEXES OF TRIS(2-(DIPHENYLPHOSPHINO)ETHYL)PHOSPHINE

Treatment of tris(2-(diphenylphosphino)ethyl)phosphine (PP3) with Me2SAuCl produces colorless [Au2(μ-PP3)2]Cl2. This crystallizes as a dichloroform solvate in the triclinic space group P1 (No. 2) with o = 13.389 (4) Å, b = 14.924 (4), c = 24.441 (8) Å, α = 72.41 (2)°, β = 74.75 (2)°, and γ = 69.22 (2)° at 130 K with Z = 2. Refinement of 8626 reflections and 507 parameters yields R = 0.052 and Rw= 0.054. The salt contains a binuclear cation in which each PP3 coordinates through three phosphorus atoms to one gold(I), while one arm forms a bridge to the other gold(I). The two golds are widely separated by 6.199 Å. Both have roughly tetrahedral geometry. The binuclear ion is resistant to reaction with the nucleophiles azide and thiocyanate but reacts readily with Me2SAuCl to form Au4Cl4(μ-PP3). Colorless needles of the dichloromethane/ethyl ether solvate of AU4CL4(μ-PP3) crystallize in the monoclinic space group P21/n (No. 14) with a = 25.393 (15) Å, b = 15.717 (13) Å, c = 27.565 (16) Å, and β = 106.16 (4)° at 130 K with Z = 4. Refinement of 3789 reflections and 368 parameters yields R = 0.082 and Rw= 0.074. There are two similar Au4Cl4(μ-PP3) molecules in the asymmetric unit. Each phosphorus in part of a nearly linear PAuCl moiety. While there are no Au-Au contacts less than 3.5 Å within either independent molecule, there are short contacts of 3.1 Å between molecules. © 1990, American Chemical Society. All rights reserved.