Incorporation of Group 11 Metal Ions into a Diplatinum Center Leading to Pt(2)M Heterotrinuclear Complexes Supported by a Tridentate Phosphine Ligand (M = Au, Ag, Cu).

Abstract

The reaction of syn-[Pt(2)(&mgr;-dpmp)(2)(XylNC)(2)](PF(6))(2) (1) with AuPF(6) yielded the Pt(2)Au trinuclear complex [Pt(2)Au(&mgr;-dpmp)(2)(XylNC)(2)](PF(6))(3) (7) in 60% yield. ()The structure was determined by X-ray crystallography to comprise a Pt(2)Au trinuclear core bridged by two dpmp ligands (7.(CH(3))(2)CO: monoclinic, P2(1)()/n (No. 14), a = 15.147(3) Å, b = 25.947(8) Å, c = 25.759(6) Å, beta = 104.10(2) degrees, V = 9818 Å(3), Z = 4, D(calcd) = 1.593 g cm(-)(3), R = 0.065, and R(w) = 0.059). An Au(I) ion is trapped by two uncoordinated phosphine units in 1 to lead a deformed Pt-Pt-Au aggregation. The Pt-Pt and Pt.Au distances are 2.708(2) and 3.045(2) Å, respectively, and the Pt-Pt.Au angle is 110.68(5) degrees. The similar Pt(2)Ag cluster, [Pt(2)Ag(&mgr;-dpmp)(2)(XylNC)(2)](PF(6))(3) (8), was also prepared by the reaction of complex 1 with AgPF(6) in 70% yield. The crystal structure is essentially identical to that of 7 (monoclinic, C2/c (No. 15), a = 18.302(6) Å, b = 25.056(6) Å, c = 47.172(9) Å, beta = 99.11(3) degrees, V = 21359 Å(3), Z = 8, D(calcd) = 1.373 g cm(-)(3), R = 0.089, and R(w) = 0.078). The Pt-Pt and Pt.Ag distances are 2.657(2) and 3.118(3) Å, respectively, and the Pt-Pt.Ag angle is 136.36(8) degrees. Reactions of 1 with CuX (X = I, Br, Cl) gave yellow complex [Pt(2)CuX(&mgr;-dpmp)(2)(XylNC)(2)](PF(6))(2) (9, X = I; 10, X = Br; 11, X = Cl), in good yield (9.Et(2)O: monoclinic, P2(1)()/c (No. 14), a = 15.048(4) Å, b = 21.922(3) Å, c = 27.840(3) Å, beta = 101.89(1) degrees, V = 8987 Å(3), Z = 4, D(calcd) = 1.641 g cm(-)(3), T = 23 degrees C, R = 0.056, and R(w) = 0.046. 10.Et(2)O: monoclinic, P2(1)()/c (No. 14), a = 14.910(4) Å, b = 21.891(7) Å, c = 27.226(8) Å, beta = 101.66(6) degrees, V = 8702 Å(3), Z = 4, D(calcd) = 1.658 g cm(-)(3), T = -95 degrees C, R = 0.042, and R(w) = 0.046. 11.Et(2)O: monoclinic, P2(1)()/c (No. 14), a = 15.037(4) Å, b = 22.081(6) Å, c = 27.449(4) Å, beta = 101.92(2) degrees, V = 8917 Å(3), Z = 4, D(calcd) = 1.585 g cm(-)(3), T = 23 degrees C, R = 0.040, and R(w) = 0.041). The Pt(2)CuX assembly forms a rhombic structure with the Pt-Pt, Pt.Cu, Cu-X, and Pt.X distances being 2.715-2.727, 2.857-2.872, 2.276-2.597, and 3.088-3.130 Å, respectively. The CuI fragment is trapped by the pendant phosphorus arms of 1. The Pt.Cu-X angle is interestingly less than 90 degrees, resulting in a relatively short interatomic distance between the terminal Pt and X atoms. A monovalent group 11 metal ion (Au(I), Ag(I), or Cu(I)), which has a d(10) configuration, was readily incorporated into the Pt(2) core, leading to a heterotrimetallic Pt(2)M aggregation.