Reactivity of [M(C∧P)(acac-O,O′)] [M = Pt, Pd; C∧P = CH2-C6H4-P(o-tolyl)2-κC,P; acac=2,4-pentanedionato] toward HgX2 (X = Br, I, CH3COO, CF3COO).: New polynuclear complexes containing Pt-Hg bonds.: Molecular structures of [{Pt(C∧P) (acac-O,O′)-HgBr(μ-Br)}2(μ-HgBr2)], an unprecedented square-planar bromomercurate complex, and [{Pt(C∧P)(μO2CCH3)2Hg(μ3-acac2--κC3,O(Hg(O2CCH3-κO}• CHCl3]2 the first complex containing asymmetric dimercurated acetylacetone

The complexes [M(C boolean AND P)(acac-O,O')] [M = Pt (1) Pd (1'); C boolean AND P = CH2-C6H4-P(o-tolyl)(2)-kappa C,P; acac = 2,4-pentanedionato] were prepared by the reaction of [M(C boolean AND P)(mu-Cl)](2) [M = Pt, Pd] with Tl(acac) and fully characterized. The reactions of [Pt(C boolean AND P)(acac-O,O')] (1) with equimolar amounts of HgX2 (X = I, Br) give the polynuclear complexes [Pt(C boolean AND P)(acac-O,O')HgI(mu-I)](2) (2) and [{Pt(C boolean AND P)(acac-O,O')HgBr(mu-Br)}(2)(mu-HgBr2)] (3) containing unsupported Pt-to-Hg donor bonds. In the pentanuclear complex 3, the central mercury atom shows an unexpected square-planar environment, unprecedented for halomercurates(II). The complex [Pt(C boolean AND P)-(acac-O,O')] (1) also reacts with Hg(O2CR)(2) (R = CH3, CF3), but in 1:2 molar ratio, to afford the neutral hexanuclear complexes [Pt(C boolean AND P)(mu-O2CR)(2)Hg(mu(3)-acac(2-)-kappa C-3,O)Hg (O2CR-kappa O)](2) [R = CH3 (4), CF3 (5)]. An X-ray study of 4 revealed that these compounds contain very short platinum-to-mercury donor bonds supported by two carboxylate groups, along with an unusual dimercurated acetylacetone moiety. The reactions of [Pd(C boolean AND P)(acac-O,O')] (1') with HgX2 (X = Br, I, CH3COO, CF3COO) proceed mainly (X = Br, CH3COO, CF3COO) with substitution of the acac-O,O' Ligand by X from the coordination environment of the palladium center to give the binuclear derivatives [Pd(C boolean AND P)(mu-X)](2) (X = Br, CH3COO, CF3COO), hindering the obtention of palladium-mercury compounds by this route.