Palladium(II) iminophosphine complexes

New complexes of general formula [PdCl2(N∧P)] (N∧P = o-Ph2PC6H4-CH=N-R; R = Me, iPr, tBu, NH-Me) and [Pd(N∧P)2](ClO4)2 (N∧P = o-Ph2PC6H4-CH=N-R; R = Me, iPr) have been prepared by directly reacting the precursor PdCl2(PhCN)2 with iminophosphines (N∧P) in 1:1 and 1:2 molar ratios respectively. When the chloro-complex [PdCl2(o-Ph2PC6H4-CH=Ni-Pr)] was treated with CF3SO3Ag in MeCN, the labile complex [Pd(o-Ph2PC6H4-CH=Ni-Pr)(MeCN)2](CF3SO3)2 was obtained in good yield. The reactivity of the new precursor towards a variety of neutral N- and P-donor ligands (py, PMe2Ph, PMePh2, PEt3, bipy, dppe, 2-thpy) has been studied. The new complexes were characterized by partial elemental analyses and by spectroscopy (i.r., 1H- and 31P-n.m.r.). The molecular structure of the aquo-complex [Pd(N∧P)(2-thpy)(H2O)](CF3SO3)2 has been determined by a single-crystal diffraction study, showing that the iminophosphine acts as a chelating ligand with coordination around the palladium atom slightly distorted from square-planar geometry.