16971-53-2

Upstream product

• 16940-66-2 sodium tetrahydroborate 
• 15318-31-7 bis(triphenylphosphine)iridium(I) carbonyl chloride 
• 16971-53-2 fac-{IrH₃(PPh₃)2(CO)} 
• 187225-26-9 trans-Ir(PPh3)2(η(1)-indolyl)(CO) 
• 1333-74-0 parahydrogen 
• 33541-67-2 carbonylhydridotris(triphenylphosphine)iridium(I) 
• 67-56-1 methanol 
• 24846-85-3 IrHCl2(PPh3)3 
• 17000-11-2 IrCl(H)₂(CO)(PPh₃)₂ 
• 17250-59-8 HIr(PPh₃)2(CO)2 
• 1333-74-0 hydrogen 
• 98720-65-1 trans-t-BuOIr(CO)(PPh₃)2 
• 94070-39-0 trans-n-PrOIr(CO)(PPh₃)2 
• 94070-40-3 trans-PhOIr(CO)(PPh₃)2 

Downstream Products

• 16971-53-2 fac-{IrH₃(PPh₃)2(CO)} 
• 33541-67-2 carbonylhydridotris(triphenylphosphine)iridium(I) 
• 16971-53-2 mer,cis-IrH₃(CO)(PPh₃)2 
• 207409-67-4 fac-cis-IrH₃(CO)2(PPh₃) 
• 207409-67-4 mer-trans-IrH₃(CO)2(PPh₃) 
• 16971-53-2 mer,trans-IrH₃(CO)(PPh₃)2 
• 15318-31-7 bis(triphenylphosphine)iridium(I) carbonyl chloride 
• 75494-06-3 IrH₂[Si(OC₂H₅)3](CO)(P(C₆H₅)3)2 
• 84602-19-7 (η2-styrene)carbonylhydridobis(triphenylphosphine)iridium(I) 

Relevant academic research and scientific papers

Cooperative or Oxidative Hydrogen Addition to 2-Hydroxypyridonate Iridium Complexes: Dependence on Oxidation State

Iridium(III)–pyridone complexes are commonly found to react in a cooperative and redox-neutral manner with dihydrogen and alcohols. In this work, the reactivity preferences of IrI–pyridone complexes were investigated under a variety of conditions. We have found that, in contrast to IrIII–pyridones, IrI–pyridone complexes display a strong preference to react non-cooperatively. With a new chelating 2-hydroxy-8-diphenylphosphinoquinoline ligand that does not dissociate after hydrogen addition, oxidative addition is still preferred. In the preparation of mono- and bidentate neutral and anionic pyridone ligands, Vaska's complex was used as a point of reference. We expect these findings to have implications for catalyst development in the field of metal–ligand cooperation.

The Origin of the Directing Effect in H2 Addition to Square-Planar d8 Complexes

Hydrogen adds to square-planar d8 complexes of the Vaska type to give oxidative addition products in which the H2 has added parallel to the X-Ir-CO axis.In principle, however, addition perpendicular to this axis should also be possible.Three models have been discussed to account for the apparent preference for parallel adducts.We show that in contrast to the chloro complex (X = Cl, parallel adduct formed), the methyl, phenyl, or hydride analogues give perpendicular adducts.In one case (X = Ph), the perpendicular adduct is formed at -80 deg C, but rearranges to the parallel adduct on warming via reductive elimination of H2 and readdition.These findings seem to invalidate the previous theoretical models that have been proposed to explain the direction of H2 addition.A new one is suggested that covers all the data gathered up to now.

Mechanism of the Reaction of Hydrogen and Phenylacetylene with IrH(CO)(PPh3)3. Kinetic Evidence for the Co-ordinatively Unsaturated IrH(CO)(PPh3) Species in Solution as Reactive Intermediates and for the Reaction of Hydrogen with the Co-ordinatively Saturated IrH(CO)(PPh3)3 Species

A kinetic study of the reaction between IrH(CO)(PPh3)3 and H2 or PhCCH provided evidence for the existence of the co-ordinatively unsaturated intermediate IrH(CO)(PPh3) in solution, as well as a direct attack of hydrogen on the co-ordinatively saturated IrH(CO)(PPh3)3.

Using: Para hydrogen induced polarization to study steps in the hydroformylation reaction

A range of iridium complexes, Ir(η3-C3H5)(CO)(PR2R′)2 (1a-1e) [where 1a, PR2R′ = PPh3, 1b P(p-tol)3, 1c PMePh2, 1d PMe2Ph and 1e PMe3] were synthesized and their reactivity as stoichiometric hydroformylation precursors studied. Para-hydrogen assisted NMR spectroscopy detected the following intermediates: Ir(H)2(η3-C3H5)(CO)(PR2R′) (2a-e), Ir(H)2(η1-C3H5)(CO)(PR2R′)2 (4d-e), Ir(H)2(η1-C3H5)(CO)2(PR2R′) (10a-e), Ir(H)2(CO-C3H5)(CO)2(PR2R′) (11a-c), Ir(H)2(CO-C3H7)(CO)2(PR2R′) (12a-c) and Ir(H)2(CO-C3H5)(CO)(PR2R′)2 (13d-e). Some of these species exist as two geometric isomers according to their multinuclear NMR characteristics. The NMR studies suggest a role for the following 16 electron species in these reactions: Ir(η3-C3H5)(CO)(PR2R′), Ir(η1-C3H5)(CO)(PR2R′)2, Ir(η1-C3H5)(CO)2(PR2R′), Ir(CO-C3H5)(CO)2(PR2R′), Ir(CO-C3H7)(CO)2(PR2R′) and Ir(CO-C3H5)(CO)(PR2R′)2. Their role is linked to several 18 electron species in order to confirm the route by which hydroformylation and hydrogenation proceeds.

New perspectives in hydroformylation: A para-hydrogen study

NMR studies on the reaction of Ir(CO)(PPh3)2(η 3-C3H5) with para-H2 and CO enable the complete mapping of the hydroformylation mechanism for an iridium monohydride catalyst via the detection of species which include iridium acyl and alkyl dihydride intermediates.

The effect of ancillary ligands on intramolecular proton-hydride (NH?HIr) bonding in complexes of iridium(III)

The reaction of the trihydride IrH3(PPh3)3 with HBF4 in the presence of pyridinethione (SpyH) affords a dihydrido SpyH complex [IrH2(η1-SpyH)(PPh3)3](BF 4) (1). Complex 1 undergoes a substitution of one of the PPh3 ligands by another SpyH to produce [IrH2(η1-SpyH)2(PPh3) 2](BF4) (2). Complex 2 slowly eliminates a dihydrogen molecule to form a known monohydrido complex [IrH(η1-SpyH)(η2-Spy)(PPh3) 2](BF4) under mild conditions. [IrH(CO)(η1-SpyH)2(PPh3) 2](BF4)2 (3) is obtained from the reaction of known IrH3(CO)(PPh3)2 with HBF4 in the presence of SpyH. The properties of the NH?HIr proton-hydride bonds (also known as dihydrogen bonds) in complexes 1-3 are characterized in solution by T1 NMR measurements and in the solid state by IR measurements and single crystal X-ray diffraction. They are compared with properties of three related complexes to understand the effect of the ancillary ligands on the strength of this non-classical bond. Stronger proton-hydride bonds are formed in complexes with PCy3 co-donor ligands in comparison with complexes with PPh3 co-donor ligands. The strength of proton-hydride bonds is decreased in complexes containing more PPh3 or CO ligands. The best indicators of H?H bond strength are Av values from IR and the N?Ir distance from the X-ray structures.

Parahydrogen enhanced NMR studies on thermally and photochemically generated products from [IrH3(CO)(PPh3)2]

Parahydrogen induced polarisation is used to enable the rapid NMR characterisation of thermally and photochemically generated complexes of general formula [IrH3(CO)3-x(PPh3)x] (x = 1-3).

Formation of carbon-hydrogen and oxygen-hydrogen bonds at iridium centers: Addition of H2 and HCl to trans-RIr(CO)L2 (R = Me, OMe; L = PPh3, P(p-tolyl)3)

Reaction of trans-RIr(CO)L2 with HX (R = Me, L = P(p-tolyl)3, X = H, Cl; R = OMe, L = PPh3, X = H; R = OMe, L = P(p-tolyl)3, X = Cl results in RH and HIr(X)2(CO)L2. Low-temperature NMR spectra (1H and 31P) show that these reactions occur through oxidative-addition, reductive-elimination sequences. A normal deuterium isotope effect is observed (kH/kD = 1.4). Formation of the carbon (sp3)-hydrogen bond occurs more readily than formation of the carbon (sp2)-hydrogen bond or the oxygen-hydrogen bond. The nature of the hydrogen source (HX; X = H, Cl) does not significantly affect CH4 formation but is significant for CH3OH formation. Considering the geometric and product differences, however, the three types of bonds are formed with remarkably similar barriers.

Addition reactions and crystal structure of trans-CH3Ir(CO)(PPh3)2

The complex trans-MeIr(CO)(PPh3)2 readily undergoes addition reactions with a variety of small molecules such as H2, CO, MeO2CCH=CHCO2Me, MeO2CC≡CCO2Me, O2, CH3I, and H2C(O) to yield well-characterized products. Further reactions of the addition complexes are noted in most cases. The species trans-MeIr(CO)(PPh3)2 crystallizes in the centrosymmetric triclinic space group P1 with a = 9.2497 (9) ?, b = 9.6080 (11) ?, c = 10.4855 (14) ?, α = 72.390 (10)°, β = 88.990 (9)°, γ = 69.224 (8)°, V = 826.22 (16) ?3, Z = 1, and D(calcd) = 1.53 g cm-3 for mol wt 759.9. Diffraction data (Mo Kα 2θ = 4.5-50.0°) were collected with a Syntex P21 automated four-circle diffractometer and refined to RF = 1.8% and RwF = 2.1% for the 2922 independent reflections (none rejected). The molecule lies on a center of symmetry and is disordered with CO and Me ligands occupying square-planar sites rigorously coplanar with the iridium atom. The Ir-P distances are each 2.300 (1) ?; estimated Ir-CO and Ir-Me distances are ～1.835 and ～2.17 ?, respectively.

Preparation and interconversion of two isomeric iridium trihydrides

The preparation, separation, and structural characterization of a,b,c-trihydrido-f-carbonylbis(triphenylphosphine)iridium(III) and a,b,f,-trihydrido-d-carbonylbis(triphenylphosphine)iridium(III) are described. The kinetics of interconversion of the two isomers and of the displacement of H2 from both isomers by triphenylphosphine have been measured and indicate that interconversion occurs via reversible reductive elimination/oxidation sequence. Both the isomerization and substitution reactions are postulated to involve the intermediate IrH(CO)P2. The relationship of the present results to other studies of the stereochemistry of oxidative additions to square-planar iridium(I) complexes is discussed.