Functionalized palladium(II) cyclometallated complexes. Crystal and molecular structures of [Pd{3-(CHO)C 6H 3C(H)NCy}(μ-O 2CMe)] 2 and [Pd{3-(CHO)C 6H 3C(H)NCy}(Cl)(PR 3)] (PR 3=PEtPh 2, and PEt 2Ph)

Abstract

The crystal structure of the cyclometallated acetato-bridged complex [Pd{3-(CHO)C 6H 3C(H)NCy}(μ-O 2CMe)] 2, 1 is reported. Each palladium atom is C, N-bonded to the chelating Schiff base ligand. The molecular configuration corresponds to the anti isomer, with the cyclopalladated moieties in an ‘open-book’ disposition. Treatment of 1 with aqueous sodium chloride gave the chloro-bridged compound 2, which when treated with tertiary phosphines yielded complexes 3 and 4. The crystal structures of complexes [Pd{3-(CHO)C 6H 3C(H)NCy}(Cl)( PR 3)] (PR 3=PEtPh 2, 3 and PEt 2Ph, 4) are also reported. In both complexes the palladium atom is bonded in a slightly distorted square-planar coordination to a carbon and a nitrogen atom of the Schiff base, a chlorine atom and to the phosphorus atom of the phosphine ligand. The reaction of the chloro-bridged complex 2 with the tertiary diphosphines Ph 2PCH 2PPh 2 (dppm) and Ph 2P(CH 2) 2PPh 2 (dppe) in a 1:2 molar ratio, and ammonium hexafluorophosphate, yielded the mononuclear cyclometallated complexes [Pd{3-(CHO)C 6H 3C(H)NCy}{Ph 2PCH 2PPh 2- P, P}][PF 6], 5 and [Pd{3-(CHO)C 6H 3C(H)NCy}{Ph 2P(CH 2) 2PPh 2- P, P}][PF 6], 6, respectively.