Methylmercury(II) and phenylmercury(II) chelated complexes with the ligand tris(2-diphenylphosphinoethyl)phosphine: synthesis, X-ray diffraction and NMR studies

The reaction of methyl and phenylmercury ions with the ligand tris(2-diphenylphosphinoethyl)phosphine, pp,, allowed the isolation of the complexes [(pp(3))HgR]BF4 (R = Me, Ph). The X-ray crystal structure of the methyl derivative established that in the cation the metal atom is coordinated to the central phosphorus atom of the tripod pp(3) ligand and to the methyl group. Two terminal phosphorus atoms of the ligand are additionally linked to the metal throught secondary bonding interactions. P-31- and Hg-199-NMR spectra indicated that the coordination of terminal phosphorus atoms of pp, to the mercury atom occurs also in solution.