Reactivity of [M(C∧P)(S₂C-R)] (M = Pd, Pt; C∧P = CH₂-C₆H₄-P(o-tolyl)₂-κC,P; R = NMe₂, OEt) toward HgX₂ (X = Br, I). X-ray Crystal Structures of [Pt{CH₂-C₆H₄P(o-tolyl)₂-κC,P}(S₂CNMe₂)HgI(μ-I)]₂ and [PdBr(S₂COEt){μ-P(o-tolyl)₂-C₆H₄-CH₂-}HgBr]·0.5HgBr₂·C₂H₄Cl₂

Abstract

The reaction of the complexes [Pt(C∧P)(S2C-R)] (C∧P = CH2-C6H4-P(o-tolyl)2-κC,P, R = NMe2, OEt) with an equimolar amount of HgX2 (X = Cl, Br) gives the tetranuclear derivatives [Pt(C∧P)(S2C-R)HgX(μ-X)]2 [R = NMe2, X = Br (3), I (4); R = OEt, X = Br (5), I (6)] containing Pt→Hg donor−acceptor bonds. The reaction of [Pd(C∧P)(S2CNMe2)] with HgI2 affords the complex [Pd(C∧P)(S2CNMe2)HgI(μ-I)]2 (9) similar to the complexes 3−6; by contrast the reaction of [Pd(C∧P)(S2C-R)] (R = NMe2, OEt2) with HgBr2 leads to the corresponding dinuclear complexes [PdBr(S2C-R)(μ-C∧P)HgBr] [R = NMe2 (10), OEt (11)] with the didentate C∧P cyclometalating ligand, −CH2-C6H4-P(o-tolyl)2-C,P (resulting from the C−H activation of the P(o-tolyl)3) acting in an unprecedented bridging mode. Compound 4 (C24H26HgI2NPPtS2) crystallizes in the triclinic system, space group P1̄: a = 9.5755(11) Å, b = 11.1754(12) Å, c = 14.504(2) Å, α = 84.826(5)°, β = 81.611(7)°, γ = 68.606(9)°, V = 1428.5(3) Å3, and Z = 1. Compound 11·0.5 HgBr2·C2H4Cl2 (C24H25Br2HgOPPdS2·0.5 HgBr2·C2H4Cl2) crystallizes in the monoclinic system, space group P21/c: a = 15.571(2) Å, b = 10.7425(10) Å, c = 19.655(2) Å, β = 94.741(12)°, V = 3276.5(5) Å3, and Z = 4.