New mono- and bis(pentafluorophenyl)palladium(II) complexes with iminophosphine ligands. Crystal structure of [Pd(C6F5)(SC6H5)(o-Ph2PC6H4-CH=(NPr)-Pr-i)]

The synthesis of new mono- and bis(pentafluorophenyl) derivatives of pallad ium(II) with the mixed-donor bidentate ligands o-Ph2PC6H4-CH=NR (RN-P) has been achieved. The new complexes of general formula [Pd(C6F5)(2)(RN-P)] [R = Me (1). Et (2), Pr-n (3) Pr-i (4), Bu-t (5), Ph (6), NH-Me (7)] and [Pd ( C6F5)Cl(RN-P)] [R = Me (8), Pr-i (9). NH-Me (10)] have been, respectively. prepared by reaction between the labile precursors cis-[Pd(C6F5)(2)(PhCN)(2 )] or [{Pd(C6F5)(tht)(mu -Cl)}(2)] (tht = tetrahydrothiophene) and the corr esponding iminophosphines. Complex (9) undergoes metathetical exchange of c hloride with anionic monodentate ligands when reacting with alkaline salts, giving the complexes of formula [Pd(C6F5)X('PrN-P)] [X = Br (11), I (12), CN (13), SCN (14), SC6H5 (15), p-SC6H4Me (16), p-SC6H4NO2 (17), OMe (18)]. Furthermore, when the chloropentafluorophenyl complex (9) was treated with silver trifluoromethanesulfonate in the presence of tertiary phosphines, th e cationic derivatives [Pd(C6F5)(L)('PrN-P)](CF3SO3) [L = PEt3 (19), PMe2Ph (20), PMePh2 (21)] were obtained in good yield. The new complexes were cha racterized by partial elemental analyses and spectroscopic methods (IR, H-1 , F-19 and P-31 NMR). The molecular structure of complex (15) has been dete rmined by a single-crystal diffraction study, showing that the iminophosphi ne act as chelating ligand with coordination around the palladium atom slig ht distorted from the square-planar geometry, (C) 2001 Elsevier Science B.V . All rights reserved.