Synthetic and structural studies of methyl- and phenylpalladium(II) complexes of poly(pyrazol-l-yl)borates, and the eta3-allylpalladium(II) complex Pd(eta3-C3H5){(pz)3BH-N,N'}

Abstract

The poly(pyrazol-l-yl)borate complexes PdMe{(pz)3BR-N,N'}(PPh3) (R = H, pz) are formed on the reaction of [PdMe(SMe2)(mu-I)]2 with K[(pz)3BR] in the presence of PPh3 and TIPF6, and the phenylpalladium(II) analogues are formed directly from PdIPh(tmeda)(tmeda = N,N,N',N'-tetramethylethylenediamine) and K[(pz)3BR] in the presence of PPh3. X-ray diffraction studies of PdR{(pZ)3B-N,N'}(PPh3) (R = Me, Ph) and PdPh{(pz)3BH-N,N'}(PPh3) reveal square planar geometry for palladium with the poly(pyrazol-l-yl)borate ligands in bidentate mode. The structure of Pd(eta3-C3H5){(pz)3BH-N,N'} has also been determined, and it contains a bidentate tris(pyrazol-l-yl)borate group with the eta3-allyl group forming a dihedral angle of 125.5(2.1)° with the PdN2 plane. In both PdPh{(pz)3BH-N,N'}(PPh3) and Pd(eta3-C3H5){(pz)3BH-N,N'} the uncoordinated pyrazole group lies above the coordination plane.