77450-41-0Relevant academic research and scientific papers
Coordination chemistry of methylmercury(II). Synthesis, 1H NMR, and crystallographic studies of cationic complexes of MeHgII with ambidentate and polydentate ligands containing pyridyl and N-substituted imidazolyl donors and involving unusual coordination geometries
Canty, Allan J.,Chaichit, Narongsak,Gatehouse, Bryan M.,George, Edwin E.,Hayhurst, Glen
, p. 2414 - 2422 (2008/10/08)
Complexes [MeHgL]NO3 (L = 4,4′,4″-triethyl-2,2′:6′,2″-terpyridyl (Et3terpy), terpy, bis(2-pyridyl)methanes ((py)2CH2's), (py)2CMe2, (py)2CEt2, tris(2-pyridyl)methane, several N-alkylimidazoles, N-(2-pyridyl)imidazole, and N-methyl-2-(2-pyridyl)imidazoles) are obtained from addition reactions in acetone. Proton magnetic resonance spectroscopy is used to deduce coordination behavior of potential uni- or polydentate ligands in methanol, indicating that Et3terpy, terpy, (py)2CH2's, and N-methyl-2-(2-pyridyl)imidazoles act as bidentates to give three-coordinate mercury, but (py)2CR2 (R = Me, Et) are present as unidentates. A linear relation is obtained between 2J(1H-199Hg) for [MeHgL]+ and protonation constants for L, where L = N-alkylimidazoles, and the relation is similar to that obtained previously for L = pyridines. The ambidentate ligand N-(2-pyridyl)imidazole binds to mercury via the imidazole ring. Crystalline [MeHg((py)2CH2)]NO3 has (py)2CH2 present as a bidentate ligand with T-shape coordination geometry based on a dominant C-Hg-N moiety [Hg-N = 2.16 (1) ?, C-Hg-N = 172 (1)°] and a weaker Hg-N′ bond [2.75 (2) ?]. [Crystal data: space group P21/n, Z = 4, a = 16.875 (2) ?, b = 8.540 (1) ?, c = 9.353 (1) ?, β = 96.544 (8)°, R = 0.054 for 1142 reflections having I ≥ 3σ(I).] Crystalline [MeHg(Et3terpy)]NO3 has Et3terpy present as a tridentate ligand with MeHgII bonded strongly to the central nitrogen [2.26 (2) ?, C-Hg-N = 171 (1)°] and weakly to the terminal nitrogens [2.51 (2), 2.61 (2) ?]. [Crystal data: space group P21/n, Z = 4, a = 9.115 (2) ?, b = 15.725 (3) ?, c = 15.566 (3) ?, β = 94.465 (14)°, R = 0.063 for 1286 observed intensifies having I ≥ 3σ(I).] Syntheses of new ligands containing pyridyl and N-methylimidazolyl donor groups are described.
