ABSTRACT
In the title two-coordinate silver compound, [Ag(C(3)H(9)P)(2)]PF(6), the cation has crystallographically imposed mirror symmetry, and approximates very closely to 3m (D(3d)) symmetry with fully staggered methyl groups in the solid state. The Ag atom has a nearly linear coordination geometry, with a P[bond]Ag[bond]P angle of 178.70 (4) degrees. The Ag[bond]P bond lengths are 2.3746 (12) and 2.3783 (12) A, which are significantly longer than the Au[bond]P bond length of 2.304 (1) A in the analogous two-coordinate gold cation. The lack of intramolecular steric effects within the present cations containing trimethylphosphine (cone angle 118 degrees), compared with those in known cations containing trimesitylphosphine (cone angle 212 degrees), provides a better comparison of M[bond]P distances and thus more conclusive evidence that Au really is smaller than Ag.
ABSTRACT
The bidentate phosphine ligand Ph(2)PCH(2)Si(CH(3))(2)CH(2)PPh(2) (L(2)), an analogue of 1,3-bis(diphenylphosphino)propane (dppp), coordinates to mercury(II) salts to form complexes of the general formula [HgX(2).L(2)] (X = Cl, Br, I, NCS). Infrared, Raman, and multinuclear ((1)H, (13)C, (31)P, (199)Hg) NMR spectroscopic studies show that the complexes exhibit four-coordinate pseudotetrahedral metal geometry. [HgI(2)(Ph(2)PCH(2)Si(CH(3))(2)CH(2)PPh(2))] (1) crystallizes in the monoclinic space group P2(1)/n with a = 13.028(2) Å, b = 17.402(5) Å, c = 13.849(2) Å, beta = 90.635(14) degrees, V = 3139.5(11) Å(3), and Z = 4. The structure contains a tetrahedral mercury center with the phosphine ligand bound in a bidentate fashion: Hg-P 2.511(2), 2.515(2) Å; P-Hg-P 105.28(6) degrees. The complex [HgCl(2)](2).L(2) has also been generated via a 2:1 metal:phosphine stoichiometry.
