INTERACTION OF METHYLMERCURY(II) WITH THE BIFUNCTIONAL LIGAND O-DIPHENYLPHOSPHINOBENZOATE, DPB - SYNTHESIS AND CHARACTERIZATION OF [(DPB)HGME] AND [(DPBO)HGME], DPBO = O-DIPHENYLPHOSPHINOXIDEBENZOATE

The complex [(dpb)HgMe] (1) is obtained by reaction of MeHg(OH) with o -diphenylphosphinobenzoic acid (Hdpb); alternatively the solvate [(dpb )HgMe]. 0.5H(2)O . 0.5C(5)H(5)N (1bis) can be prepared by reacting MeH gCl with Hdpb and pyridine. The derivative [(dpbo)HgMe] (2), where dpb o is o-diphenylphosphinoxidebenzoate, is formed by reaction of 1 or Ib is solutions with atmospheric oxygen. Crystal data for Ibis: monoclini c, space group P2/n, a = 10.413(4), b = 9.831(3), c = 20.674(3) Angstr om, beta = 102.51(3)degrees, Z = 2. Crystal data for 2. triclinic, spa ce group P (1) over bar, a = 11.535(2), b = 12.897(5), c = 13.275(7) A ngstrom, alpha = 88.31(4), beta = 73.65(4), gamma = 85.27(4)degrees, Z = 2. In Ibis the mercury atom displays a distorted linear fashion, be ing coordinated to a methyl group and to the phosphorus atom of the dp b ligand. Two additional weaker linkages cause the packing in pairs of the molecules. In 2 the mercury is linearly linked to a methyl group and to an oxygen atom of the carboxylic group of the dpbo ligand. Also in this case the coordination around the mercury center is completed by two weaker additional bond interactions, which, involving the oxyge n atoms of the adiacent moiety, determine the dimerization of the mole cule. The multinuclear magnetic resonance spectra of 1 (or Ibis) which have been compared with those of the related complex [(PPh3)HgMe](CF3 SO3) (3) and of the solution containing 1 and CF3SO3H (molar ratio 1:1 .5), do not seem to unambigously support a dimeric configuration of th e complex in solution. (C) 1998 Elsevier Science S.A. All rights reser ved.