METAL-COMPLEXES OF DYES .6. PHOSPHINE-NIC KEL, PALLADIUM, PLATINUM COMPLEXES AND PENTAMETHYLCYCLOPENTADIENYL RHODIUM AND IRIDIUM COMPLEXES OF 2,2'-DIHYDROXYAZOARENES

The terdentate dianions of 2,2'-dihydroxyazobenzene (L(1)H), 1-(2-hydr oxy-4-nitrophenylazo)-2-naphthol (L(2)H), 1-(2-hydroxy-5-nitrophenylaz o)-2-naphthol (L(3)H) and methyl-4-(2-hydroxy-5-nitrophenylazo)-5-pyra zolone (L(4)H) form with chloro bridged complexes [(R(3)P)MCl(2)](2) ( M = Pd, Pt; R = Ph, nBu), [(eta(5)-C(5)Me(5))MCl(2)](2) (M = Ph, Ir) a nd with (nBu(3)P)(2)NiCl2 the metal dye complexes (R(3)P)ML (M = Ni, P d, Pt) and (C(5)Me(5))ML (M = Ph, Ir). The structures of (Ph(3)P)PtL(1 ) and (nBu(3)P)PdL(3) have been determined by X-ray diffraction. For t he complexes (eta(5)-C(5)Me(5))ML (M = Rh, Ir) with asymmetric metal c enters two diastereoisomers are detected by nmr spectroscopy which poi nts to the ''hydrazone'' form of the azo ligand with a pyramidalized N -atom.