Synthesis, spectroscopic and structural characterization of orthopalladated complexes with 4-phenylbenzoylmethylene triphenyl phosphorane ylide

Abstract

The orthometalated complex [Pd(mu-Cl)(C6H5C6H4C(O)CHPPh2C6H4-kappa(2)-C,C)](2) (1) was prepared by refluxing in MeOH/CH2Cl2 equimolecular amounts of Pd(OAc)(2) and (Ph)(3)PCHCOC6H4-Ph-4 (=PhBPPY) followed by addition of excess NaCl. Complex 1 reacts with 4-picoline to give the mononuclear derivative [Pd(PhC6H4COCHPPh2C6H4)(4-picoline)] (2) whose crystal structure has been determined by X-ray diffraction. The precursor complex (1) could not be isolated in a pure form, but it can be used as a starting material for the synthesis of derivatives of mononuclear cyclo-palladated complexes. Orthometallation and ylide C-coordination in complexes 3-5 were characterized by elemental analysis as well as various spectroscopic techniques.