Reactions of Organic Azides with Half-sandwich Complexes of Iridium: Preparation of Mono- and Bis(imine) Derivatives

Imine complexes [IrCl(η 5 -C 5 Me 5 )κ 1 -NH=C(H)ArP(OR) 3 ]BPh 4 (1, 2) (Ar = C 6 H 5 , 4-CH 3 C 6 H 4 ; R = Me, Et) were prepared by allowing chloro complexes [IrCl 2 (η 5 -C 5 Me 5 )P(OR) 3 ] to react with benzyl azides ArCH 2 N 3 . Bis(imine) complexes [Ir(η 5 -C 5 Me 5 )κ 1 -NH=C(H)Ar 2 P(OR) 3 ](BPh 4 ) 2 (3, 4) were also prepared by reacting [IrCl 2 (η 5 -C 5 Me 5 )P(OR) 3 ] first with AgOTf and then with benzyl azide. Depending on the experimental conditions, treatment of the dinuclear complex [IrCl 2 (η 5 -C 5 Me 5 )] 2 with benzyl azide yielded mono- [IrCl 2 (η 5 -C 5 Me 5 )κ 1 -NH=C(H)Ar] (5) and bis-[IrCl(η 5 -C 5 Me 5 )κ 1 -NH=C(H)Ar 2 ]BPh 4 (6) imine derivatives. In contrast, treatment of chloro complexes [IrCl 2 (η 5 -C 5 Me 5 )P(OR) 3 ] with phenyl azide C 6 H 5 N 3 gave amine derivatives [IrCl(η 5 -C 5 Me 5 )(C 6 H 5 NH 2 )P(OR) 3 ]BPh 4 (7, 8). The complexes were characterized spectroscopically (IR, NMR) and by X-ray crystal structure determination of [IrCl(η 5 -C 5 Me 5 )κ 1 -NH=C(H)C 6 H 4 -4-CH 3 P(OEt) 3 ]BPh 4 (2b).