Synthesis of transition-metal complexes with heterodifunctional ligands derived of NH(PPh2)(2). Crystal structure of [(eta(5)-C5Me5)RhCl{eta(2)-P, Se-Ph2PNP(Se)Ph-2}]center dot CH2Cl2

The uncoordinated P atom of the bis(diphenylphosphine)amine (dppa) ligand i n complexes [(ring)MCl2(eta (1)-P-PPh2NHPPh2)] (M = Rh, Ir. Ru) reacts with sulphur or selenium to form [(ring)MCl2(eta (1)-P-PPh2-NHP(E)Ph-2)] (E = S (1-3), Se (4-6)) containing the P-coordinated monosulphide or monoselenide ligands. The selenium derivatives have also been directly prepared from th e corresponding [{(ring)MCl2)(2)] dimer and dppaSe. Chloride abstraction fr om rhodium and ruthenium complexes gives the neutral compounds [(ring)MCl(e ta (2)-P,E-PPh2NP(E)Ph-2)] (7-10) whilst the iridium derivatives yield cati onic complexes of the general formula [{eta (5)-C5Me5)IrCl(eta (2)-P,E-PPh2 NHP(E)Ph-2)](+) (11 and 12). The crystal structure of complex [(eta (5)-C5M e5)RhCl{eta (2)-P,SePPh2NP(Se)Ph-2}] has been established by X-ray crystall ography. The rhodium atom exhibits a distorted octahedral coordination with a eta (5)-C5Me5 group occupying the centre of three octahedral sites, a bi dentate chelate P,Se-bonded ligand and a chloride atom complete the metal c oordination sphere. (C) 2001 Elsevier Science B.V. All rights reserved.