Synthesis of the Tridentate Pyridine Donor 2,6-Bispyridine (L), including Separation of meso and rac Diastereoisomers via Methylmercury(II) Derivatives, and an X-Ray Structural Study of NO3*2H2O

Article abstract of DOI:10.1039/DT9860002201

A synthesis of the new tridentate pyridine donor ligand 2,6-bis<1-phenyl-1-(pyridin-2-yl)-ethyl>pyridine, L, by reaction of 2,6-dichloropyridine with lithiated 2-(1-phenylethyl)pyridine is described.The ligand reacts with methylmercury(II) nitrate to form complexes of the meso and rac diastereoisomers of L, NO3*2H2O, which may be readily separated by fractional crystallization.The ligands meso-L and rac-L may be liberated from the complexes by reaction with cyanide ion in water.The crystal structure of the meso complex has been determined by single-crystal X-ray diffraction at 295 K and refined by least-squares methods to R = O.046 for 2 600 'observed' reflections 1/n, with a = 20.946(9), b = 14.767(4), c = 9.817(3) Angstroem, β = 91.12(2)deg, and Z = 4>.The (+) cations have irregular co-ordination geometry for the mercury atom 'HgCN3' with the ligand present as a tripodal tridentate.The central nitrogen forms the strongest bond to mercury <2.283(9)Angstroem> with C-Hg-N 166.3(5)deg, with the other nitrogen donors 2.546(11) and 2.595(10) Angstroem from mercury and forming C-Hg-N angles of 113.3(5) and 113.7(5)deg, respectively. (1)H N.mm.r. spectra for the complexes suggest that the ligand is at least bidentate in methanol.

Full text of DOI:10.1039/DT9860002201

View Article Online / Journal Homepage / Table of Contents for this issue

View Article Online

View Article Online

View Article Online