Reactions of trichlorovinylmercurials with potential non-chelating bidentate ligands. Crystal structures of [(C2Cl3)2Hg (4,4′-bipyridyl)] (1), [C2Cl3Hg(2-pyridyl thiolate)] (12) and polymeric HgBr2(2,2′-dipyridyl disulfide) (10)
作者:Norman A. Bell、Thomas Gelbrich、Michael B. Hursthouse、Mark E. Light、Annette Wilson
DOI:10.1016/s0277-5387(00)00554-4
日期:2000.12
Reactions of C2Cl3HgX (X = C2Cl3, Cl, Br) with the potential bidentate ligands, bis(diphenylphosphino)methane, 2,4'-bipyridyl, 4,4'-bipyridyl and 2,2'-dipyridyl disulfide(PySSPy), in a 2:1 molar ratio have been studied and the thermal and infrared spectral characteristics of the products have been examined. Complexes were isolated for (C2Cl3)(2)Hg and C2Cl3HgCl in all cases apart from between (C2Cl3)(2)Hg and the diphosphine. The diphosphine and 2,2'-dipyridyl disulfide formed 1:1 complexes (7, 6) with C2Cl3HgCl, whereas with (C2Cl3)(2)Hg the latter ligand formed [(C2Cl3)(2)Hg}(2)(PySSPy)] (3) which on standing formed C2Cl3HgSPy (12). 4,4'-Bipyridyl and 2,4'-bipyridyl differed in the stoichiometry of the isolated complexes. (C2Cl3)(2)Hg formed 1:1 complexes (1, 2) with both ligands whereas C2Cl3HgCl formed a 1:1 complex (4) with the former ligand but a 1:2 complex (5) with the latter. All four ligands caused disproportionation of C2Cl3HgBr with resulting isolation of the mercury(II) bromide complexes (8-11). The structure of [(C2Cl3)(2)Hg (4,4'-bipyridyl)] (1) shows that only one nitrogen is weakly coordinated to mercury so that C-Hg-C is approximately linear in the monomeric structure but there are four intramolecular chlorines closer to mercury than the sum of the van der Waals radii. The C-Hg-S angle in [C2Cl3Hg(2-pyridyl thiolate)] (12) is only slightly distorted from linearity due to secondary bonding to nitrogen. There are two weak intramolecular contacts between mercury and chlorine and two intermolecular mercury-sulfur contacts to form pairs of molecules which form double chains along the b axis. [HgBr2(2,2'-dipyridyl disulfide)] (10) is polymeric and contains four-coordinate mercury with the ligand bridging between mercury atoms via coordination to nitrogen. (C) 2000 Elsevier Science B.V. All rights reserved.