147361-44-2

Upstream product

• 147243-76-3 {(P(CH₂CH₂P(C₆H₅)2)3)Os(H)(N₂)}⁽¹⁺⁾*B(C₆H₅)4^(1-)={(P(CH₂CH₂P(C₆H₅)2)3)Os(H)(N₂)}B(C₆H₅)4 
• 147243-76-3 (P(CH₂CH₂P(C₆H₅)2)3)Os(H)(N₂)⁽¹⁺⁾*B(C₆H₅)4^(1-)={(P(CH₂CH₂P(C₆H₅)2)3)Os(H)(N₂)}B(C₆H₅)4 
• 67-63-0 isopropyl alcohol 
• 122-57-6 1-Phenylbut-1-en-3-one 

Downstream Products

• 147361-40-8 (P(CH₂CH₂P(C₆H₅)2)3)Os(H)(CO)⁽¹⁺⁾*B(C₆H₅)4^(1-)={(P(CH₂CH₂P(C₆H₅)2)3)Os(H)(CO)}B(C₆H₅)4 

Relevant academic research and scientific papers

Classical, nonclassical, and mixed-metal osmium(II) polyhydrides stabilized by the tetraphospbine P(CH2CH2PPh2)3. H/D isotope exchange reactions promoted by a strongly bound dihydrogen ligand

The cis-hydride-η2-dihydrogen complex [(PP3)OsH(η2-H2)]BPh4 (4), PP3 = P(CH2CH2PPh2)3, has been prepared by either protonation of the dihydride [(PP3)OsH2] or reaction of the novel dinitrogen complex [(PP3)OsH(N2)]-BPh4 (6) with H2. The nonclassical structure of 4 has been established in solution by variable-temperature NMR spectroscopy (1H, 31P), T1 measurements, and J(HD) values. An X-ray diffraction analysis has shown that the solid-state geometry of the compound is not inconsistent with the nonclassical assignment. Crystals of 4 are triclinic, space group P1 with a = 16.841(4) A?, b = 15.135(2) A?, c = 12.450(3) A?, α = 91.53(2)°, β = 96.07(2)°, γ = 106.75(2)°, V = 3016.23 A?3, and Z = 2. In the solid state and in solution at low temperature, [(PP3)OsH(η2-H2)]+ is octahedral and the hydride and dihydrogen ligands occupy mutually cis positions. The H2 ligand is trans to the bridgehead phosphorus of PP3. At ambient temperature, 4 is highly fluxional. The dynamic behavior of the complex in solution has been studied by variable-temperature 31P{1H} NMR spectroscopy using the DNMR3 program. A comparison of the chemical properties, in particular H2-displacement reactions, within the series [(PP3)MH(η2-H2)]+ (M = Fe, Ru, Os) leads to the conclusion that the osmium complex has the strongest interaction with the H2 ligand. Complex 4 has been found capable of reacting with (CD3)2CO to give the perdeuterated isotopomer 4-d3 via a keto-enol tautomerization reaction of acetone-d6. The isolation and characterization of the mixed osmium-gold dihydride [(PP3)OsH{η2-HAu(PPh3)}]PF6 has provided experimental evidence for the correctness of the H2 and HAu(PPh3) isolobal relationship. The dinitrogen ligand in 6 can easily be displaced by a plethora of ligands, including weak ones such as THF and acetone. The latter reagent reacts with 6 to form the first example of a stable and isolable cis-hydride-η1-ketone complex, [(PP3)OsH{η1-OC(CH3)2}]BPh 4, a suggested key intermediate in metal-assisted hydrogenation reactions of ketones.

Chemoselective hydrogen-transfer reduction of α,β-unsaturated ketones catalyzed by isostructural iron(II), ruthenium(II), and osmium(II) cis hydride η2-dihydrogen complexes

The nonclassical trihydrides [(PP3)M(H)(η2-H2)]BPh4 (M = Fe, Ru, Os) are efficient catalyst precursors for the reduction of α,β-unsaturated ketones via hydrogen-transfer from secondary alcohols [PP3 = P(CH2CH2PPh2)3]. α,β-Unsaturated ketones bearing bulky substituents at the double bond (i.e. benzylideneacetone) are chemoselectively reduced to allylic alcohols by using either the iron or the ruthenium catalyst. In contrast, the osmium system catalyzes the reduction of α,β-unsaturated ketones to saturated ketones via isomerization of the initially produced allylic alcohols. A number of reducible substrates including various unsaturated and saturated ketones, aldehydes, alkenes, and alkynes have been studied in order to get information on the steric and electronic factors which may affect the interaction of the substrate with the metal center and, thus, control the selectivity of the hydrogen-transfer reductions. Evidence is provided for the formation of an η1-O-benzylideneacetone complex of the formula [(PP3)Os(H){η1-OCMe-(CH=CHPh)}]BPh4 which has been characterized by multinuclear NMR spectroscopy. The latter compound and the related complex [(PP3)Os(H)(η1-OCMe2)]BPh4 have been used in a number of reactions. As a result, valuable information has been obtained which allows one to propose catalytic cycles for the hydrogen-transfer reduction of α,β-unsaturated ketones to unsaturated alcohols assisted by the Fe and Ru complexes, and for the isomerization of allylic alcohols to saturated ketones catalyzed by the Os complex.