Dihydrido Iridium Triisopropylphosphine Complexes From Organometallic Chemistry to Catalysis

Dihydrido Iridium Triisopropylphosphine Complexes From Organometallic Chemistry to Catalysis 

Iridium Complexes in Organic Synthesis. Edited by Luis A. Oro and Carmen Claver Copyright 2009 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim TSRN 97R-.V.S27-.H 996-1 

The complexes [lr(COD)(NCMe)(PR3)]BF4 (PR3 = P Pr3, PMe3), which are closely related to Crabtree s catalyst, also contain mixed ligands, very basic phosphines, P Pr3 or PMe3, and a nitrogen donor ligand, acetonitrile. These mixed-ligand pair combinations have been shown to be very useful for spectroscopic observations and have provided detailed information on the mechanism of reactions performed by those complexes [9, 10]. 

The [Ir(C0D)( Pr2PCH2CH20Me)]BF4 complex also catalyzes the hydrosilyla-tion of phenylacetylene with triethylsilane, to yield-along with the normal 

It is Hkely that the diene also remains coordinated during the hydrosilylation reactions of phenylacetylene with HSiEts, catalyzed by [Ir(diene)(NCMe)(PR3)]BF4 complexes [PR3 = P Pr3, PMe3 diene = 1,5-cyclo-octadiene, tetraflorobenzobarre-lene (TFB)]. However, detailed studies on the [Ir(COD)(NCMe)(PMe3)]BF4 complex show that cyclo-octadiene carmot be considered, in this case, as an ideal innocent Hgand because it transform into complexes containing cyclo-octadiene, cyclo-octadienyl or cyclo-octenyl Hgands in a variety of coordination modes, due to an 

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