Iridium Complexes of Aromatic N,O and N,N Chelating Ligands. Structures of [Ir(8OQ)(cod)], [Ir(8OQd)(cod)], [Ir2(7AI)2(cod)2] and [Ir(8OQd)(H)(EPh3)(cod)] (8OQ=8-Oxyquinolinate, 8OQd=2-Methyl-8-oxyquinolinate, 7AI=7-Azaindolate; E = Si, Sn; cod=1,5-Cyclooctadiene)

The X-ray structures of the complexes [Ir(8OQ)(1,5-cod)] (1), [Ir(8OQd)(1,5-cod)] (2) and [Ir-2(mu-7AI)(2)(1,5-cod)(2)] (3) (where 8OQ, 8OQd and 7AI are anions derived from 8-hydroxyquinoline, 2-methyl-8-hydroxyquinoline (8-hydroxyquinaldine) and 7-azaindole, respectively) are mononuclear in the case of 1 and 2, with evidence of steric strain induced by the methyl group in 2 and dinuclear in the case of 3. The oxidative addition products [Ir(8OQd)(H)(EPh3)(1,5-cod)] [E = Si (4), Sn (5)], formed by the reaction of 2 with SiHPh3 and SnHPh3, respectively, show significant conformational differences in the solid state.