Syntheses and structural characterizations of novel mono- and dinuclear iridium hydrido complexes with polydentate nitrogen donor ligands

New five mono- and dinuclear Ir hydrido complexes with polydentate nitrogen ligands, [Ir(H)(2)(PPh3)(2)(tptz)]PF6 (1), [Ir-2(H)(4)(PPh3)(4)(tptz)](PF6)(2.2)H2O (2.2H(2)O), [Ir(H)(2)(PPh3)(2)(tppz)]BF4 (3), [Ir-2(H)(4)(PPh3)(4)(tppz)](BF4)(2) (4) and [Ir-2(H)(4)(PPh3)(4) (bted)](BF4)(2).6CHCl(3) (5.6CHCl(3)), were systematically prepared by the reactions of the precursor Ir hydrido complex [Ir(H)(2)(PPh3)(2)(Me2CO)(2)]X (X=PF6 and BF4) With 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz), 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) and 1,4-bis(2,2:6,2"-terpyridine-4'-yl)benzene (bted), and their structures and properties were characterized in the solid state and in solution. Each of the Ir hydrido complexes with polydentate nitrogen ligands crystallographically described a unique coordination mode. Their H-1 NMR spectra demonstrated unusual I H NMR chemical shifts of pyridyl rings that are likely induced by the ring current effect of neighboring ligands. (C) 2004 Elsevier B.V. All rights reserved.