2030-83-3Relevant articles and documents
Selective Cobalt-Catalyzed Reduction of Terminal Alkenes and Alkynes Using (EtO)2Si(Me)H as a Stoichiometric Reductant
Raya, Balaram,Biswas, Souvagya,Rajanbabu
, p. 6318 - 6323 (2016/09/09)
While attempting to effect Co-catalyzed hydrosilylation of β-vinyl trimethylsilyl enol ethers, we discovered that, depending on the silane, solvent, and the method of generation of the reduced cobalt catalyst, a highly efficient and selective reduction or hydrosilylation of an alkene can be achieved. This paper deals with this reduction reaction, which has not been reported before in spite of the huge research activity in this area. The reaction, which uses the air-stable [2,6-bis(aryliminoyl)pyridine)]CoCl2 activated by 2 equiv of NaEt3BH as the catalyst (0.001-0.05 equiv) and (EtO)2SiMeH as the hydrogen source, is best run at ambient temperature in toluene and is highly selective for the reduction of simple unsubstituted 1-alkenes and the terminal double bonds in 1,3- and 1,4-dienes, β-vinyl ketones, and silyloxy dienes. The reaction is tolerant of various functional groups such as bromide, alcohol, amine, carbonyl, di- or trisubstituted double bonds, and water. Highly selective reduction of a terminal alkyne to either an alkene or alkane can be accomplished by using stoichiometric amounts of the silane. Preliminary mechanistic studies indicate that the reaction is stoichiometric in the silane and both hydrogens in the product come from the silane.
SYNTHESIS OF TERMINAL ALKENES FROM INTERNAL ALKENES VIA OLEFIN METATHESIS
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Page/Page column 41-42; 51, (2008/06/13)
This disclosure relates generally to olefin metathesis, and more particularly relates to the synthesis of terminal alkenes from internal alkenes using a cross-metathesis reaction catalyzed by an olefin metathesis catalyst. According to one aspect, for example, a method is provided for synthesizing a terminal olefin, the method comprising contacting, in the presence of a ruthenium alkylidene metathesis catalyst, an olefinic substrate comprised of at least one internal olefin with a cross metathesis partner comprised of an alpha olefinic reactant, under reaction conditions effective to allow cross-metathesis to occur, wherein the reaction conditions include a reaction temperature of at least 35 °C. The methods, compositions, reactions and reaction systems herein disclosed have utility in the fields of catalysis, organic synthesis, and industrial chemistry.
Transition Metal-catalysed Elimination of Unactivated Sulfones
Gai, Yonghua,Jin, Liren,Julia, Marc,Verpeaux, Jean-Noel
, p. 1625 - 1626 (2007/10/02)
Lithiated tert-butyl alkyl sulfones undergo an easy elimination in the presence of catalytic amounts of bisacetylacetonatopalladium, thus leading to desulfonylated alkenes.
