Preparation of phosphinoferrocene carboxamides from isocyanates. Synthesis and structural characterisation of palladium(II) and platinum(II) complexes with 1′-(diphenylphosphino)-1-(N-phenylcarbamoyl) ferrocene

The reaction of in situ generated 1'-(diphenylphosphino)-1-lithioferrocene with isocyanates RNCO affords the respective phosphino-carboxamides Ph(2)PfcCONHR (fc = ferrocene-1,1'-diyl, R = cyclohexyl (2), and Ph (3)) in moderate yields. The coordination behaviour of 3 chosen as a representative was studied in palladium(II) and platinum(II) complexes. Depending on the metal precursor and the reaction conditions, the following compounds featuring this ligand as a P-monodentate or an O,P-chelating donor were isolated and characterised by spectroscopic methods (IR, multinuclear NMR and electrospray ionisation MS): trans-[PdCl(2)(3-kappa P)(2)] (5), trans-[PtCl(2)(3-kappa P)(2)] (6), cis-[PtCl(2)(3-kappa P)(2)] (7), [SP-4-4]-[(L(NC))PdCl (3-kappa P)] (8; L(NC) = 2-[(dimethylamino-kappa N)methyl]phenyl-kappa C(1)), and [SP-4-3]-[(L(NC))PdCl(3-kappa(2)O,P)]SbF(6) (9). Besides, the crystal structures of a phosphine oxide resulting by oxidation of 2, viz Ph(2)P(O)fcCONHCy (4), and of complexes 5 center dot 2Et(2)O and 9 have been determined by single-crystal X-ray diffraction analysis. (C) 2010 Elsevier B. V. All rights reserved.