H-1-NMR STUDY OF THE FACTORS AFFECTING THE INTRA-MOLECULAR INTERACTION BETWEEN THE PHENYL RINGS AND THE MERCURY(II) ION OF SEVERAL METHYLMERCURY(II) COMPLEXES CONTAINING SUBSTITUTED PHENYL GROUPS

Complexes of methylmercury(II) ion have been prepared with several homologous series of ligands which contain phenyl rings: (1) C6H5(CH2)nX(X = NH2, S-, n = 1, 2, 3; and X = CO-2, n = 0, 1, 2) and (2) p-R-C6H4(CH2)n-1 CH(NH2)CO-2 (R = H, n = 2, 3; R = OH, n = 2). The observation of a high field shift of the [MeHg]+ 1H nmr resonance is interpreted as an anisotropic shielding effect due to an intramolecular interaction between the mercury(II) ion and the phenyl ring. Such an interaction is only observed for series (1) when X = NH2 or S- and n = 1 or 2. In the case of the N-bound methyl(L-tyrosinato)mercury(II), there is fairly good agreement between the crystal structure and that observed in solution, as estimated from the anisotropic shift and conformational analysis based on the backbone vicinal coupling constants. A similar conformational analysis is reported for the complex formed with L-3- phenylalanine. © 1979.