Five-membered ring chelate complexes of Ni(II), Pd(II) and Pt(II) derived of di-(2-pyridyl)-N-ethylimine

Abstract Cis -diaquobis{di-(2-pyridyl)- N -ethylimine}nickel(II) chloride ( 2 ) was obtained from the reaction of di-(2-pyridyl)- N -ethylimine ( 1 ) and [NiCl 2 dppe] [dppe =  cis -1,2-bis(diphenylphosphino)ethylene] in a 2:1 ratio in hot acetonitrile. C is -dichloro{di-(2-pyridyl)- N -ethylimine}palladium(II) ( 3) and cis- dichloro{di-(2-pyridyl)- N -ethylimine}platinum(II) ( 4) complexes were obtained from the reaction of MCl 2 (M = Pd, Pt) and ( 1 ) in equimolar ratio in hot acetonitrile. Compounds 1–4 were characterized by IR spectroscopy, elemental analysis, and mass spectrometry; the complexes 3 and 4 were characterized in solution by NMR. In addition, solid state structures of compounds 1 – 4 were determined using single crystal X-ray diffraction analyses. X-ray diffraction data of the complexes 3 and 4 showed a distorted square planar local geometry at palladium and platinum atoms with the chlorine atoms in a cis -coordination; in 2 a local octahedral geometry at nickel atom was observed. Complexes 3 and 4 are arranged as dimers with a M⋯M distance of 3.4567(4) A (M = Pd) and 3.4221(4) A (M = Pt), respectively; 2 consists of units linked by intermolecular hydrogen bonding.