| dc.description.abstract | The product of the reaction between PtCl2 and APPY (APPY = acetylmethylenetriphenylphosphorane, (C6H5)3PCHC(O)CH3), upon heating a 1:2 mole ratio at reflux in acetonitrile for 44 h, was originally formulated as Pt(APPY)2C12 (1) on the basis of elemental analysis and infrared and proton NMR spectral data. However, this product has now been shown by X-ray crystallography to have undergone orthometalation
of an APPY ligand and dimerization to form [Pt(u-Cl)CH3COCHP(C6H4)(C6H6)2]2 (2). The APPYH+Cl- formed in the process was identified by its IR, lH, 13C, and 31P NMR spectra and removed by washing the original sample with water. Yellow monoclinic crystals of compound 2 and two molecules of deuteriochloroform, space group C62H-C2/c were obtained by slow evaporation of a deuteriochloroform solution of the original reaction product. The unit-cell parameters at 26 degrees C are a = 21.33 (1) A, b = 18.453 (3) A, c = 14.337 (6) A, beta = 122.93 (2)O, and Z = 4. The structure has been refined to an R index on F of 0.070 for 3214 observations and 263 parameters. The two platinum atoms and the two chlorine atoms of compound 2 are planar, due to a crystallographically imposed inversion center (i) located between the two platinum atoms and the two bridging chlorine atoms. The coordination about each of the platinum atoms is square planar with a platinum-to-platinum nonbonding distance of 3.599 A. The two deuteriochloroform molecules are weakly interacting with the carbonyl oxygen of the ortho-metalated APPY ligand, 0.-D = 2.339 A. The ortho-metalating APPY ligand is puckered, as would be expected for a five-membered chelate containing only single bonds. The significant 'H, I3C, and 31P NMR and IR spectral data for this compound are also discussed. | en_US |
