Energy transfer in classical trajectories of atomic-diatomic molecule collisions Platinum(ll) complexes of substituted pyridine and pyrazole derivatives

Abstract

A series of new platinum(II) halo complexes of substituted pyridines and pyrazoles: <i>[trans- </i>PtCI₂(C₇H₇N)₂], [<i>trans</i>-PtCI₂(C₃H₄N₂)₂], [<i>trans</i>-PtCI₂(C₆H₇N)₂] and [<i>trans-</i>PtCl₂(C₄H₆N₂)₂] has been synthesized, and the complexes have been characterised on the basis of their IR, ¹H NMR, UV/vis and elemental analysis data. <i>Trans</i>-dichloroplatinum(II) complexes of nitrogen cyclic compounds have been prepared through the reaction of K₂[PtCl₄] with the corresponding ligands in water or a mixture of water and an organic solvent. The coordination reaction of 3- or 4-substituted pyridine is complete within 10 h and the yields are more than 60%, but that of 2-substituted pyridine requires a longer time (15 h) and the yields are low (44%). Platinum complexes of pyridine with a vinyl group at the <i>ortho </i> position could not be obtained, but those with a methyl or a vinyl group at the <i>para </i> position have been obtained. Each complex has a <i>trans </i> square-planar structure, the platinum being coordinated by two halogen and two nitrogen atoms and lying at a centre of symmetry.