23582-03-8Relevant articles and documents
A Mild One-Pot Reduction of Phosphine(V) Oxides Affording Phosphines(III) and Their Metal Catalysts
Kapu?niak, ?ukasz,Plessow, Philipp N.,Trzybiński, Damian,Wo?niak, Krzysztof,Hofmann, Peter,Jolly, Phillip Iain
supporting information, p. 693 - 701 (2021/04/06)
The metal-free reduction of a range of phosphine(V) oxides employing oxalyl chloride as an activating agent and hexachlorodisilane as reducing reagent has been achieved under mild reaction conditions. The method was successfully applied to the reduction of industrial waste byproduct triphenylphosphine(V) oxide, closing the phosphorus cycle to cleanly regenerate triphenylphosphine(III). Mechanistic studies and quantum chemical calculations support the attack of the dissociated chloride anion of intermediated phosphonium salt at the silicon of the disilane as the rate-limiting step for deprotection. The exquisite purity of the resultant phosphine(III) ligands after the simple removal of volatiles under reduced pressure circumvents laborious purification prior to metalation and has permitted the facile formation of important transition metal catalysts.
Synthesis of aldehydes from alcohols
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, (2008/06/13)
A catalyst has been found for the low pressure hydroformylation of alcohols to produce aldehydes. This catalyst consists of a rhodium containing compound, an iodide containing compound, and a chelating Group V compound, which is used alone or in combination with a monodentate, Group V compound. It is the first rhodium-based catalyst that generates acetaldehyde via hydroformylation of the methanol. The reaction is typically carried out at 160°-180° C. and 1000-2000 psi. The acetaldehyde rate and selectivity are 1-5 Mhr-1 and 50-75%. Conventional cobalt catalysts require operating pressures of at least 3000-6000 psi in order to obtain reasonable productivities.
