| Abstract
| - Reaction of o-(diphenylphosphino)(N-benzylidene)aniline (P∼N) with [Ir(COD)Cl]2 affords thesubstitution product [(P∼N)Ir(COD)Cl] (1). Treatment of 1 with AgBF4 yields the cyclometalated iridiumhydride complex [P,N,C-(P∼N)Ir(COD)H]BF4 (2). On the other hand, under atmospheric pressure ofCO, carrying out the substitution of [Ir(COD)Cl]2 with P∼N results in the formation of [P,N,C-(P∼N)Ir(CO)HCl] (5). Conversion of 4 into 5 can be achieved by the reaction of 4 with CO in the presence oftetraethylammonium chloride. Both 4 and 5 are characterized by spectroscopic and X-ray structuralanalyses. All iridium complexes are not good catalysts for hydroamination. However, the combinationof 5 with NaB[3,5-C6H3(CF3)2]4 (denoted as NaBArF4) provides a potent catalytic system for both intra-and intermolecular hydroamination of alkynes. Intramolecular reaction of o-(2-phenylethynyl)anilinesproduces the corresponding indoles in good yields. Furthermore, intermolecular hydroamination takesplace smoothly to generate the imine intermediates, which could be subsequently reduced by triethylsilaneusing the same catalyst, giving N-silylated amines. However, the N-silylated amines readily hydrolyze toproduce secondary amines.
- Hydridoiridium(III) complexes catalyze both intra- and intermolecular hydroamination of alkynes.
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