55258-76-9Relevant articles and documents
Photo-Mediated Decarboxylative Giese-Type Reaction Using Organic Pyrimidopteridine Photoredox Catalysts
El-Hage, Firas,Sch?ll, Christopher,Pospech, Jola
supporting information, p. 13853 - 13867 (2020/12/15)
The decarboxylative Giese-type reaction offers a versatile methodology for the radical alkylation of electron-deficient alkenes. Photo-mediated variants often require a pre-activation of carboxylic acids and/or employment of costly transition-metal photocatalysts. Herein, we present a metal-free photocatalyzed decarboxylative Giese-type addition to electron-deficient alkenes using pyrimidopteridine N-oxides as organic photoredox-active catalysts. This protocol comprises mono-, di-, and trisubstituted aliphatic, α-amino, and α-oxy acids as well as a variety of electron-deficient alkenes. Moreover, post-synthetic derivatization and applications are presented.
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.
Anti-inflammatory composition and method containing 2-fluoro-4-isopropylbiphenyl
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, (2008/06/13)
Novel substituted aromatic hydrocarbons and ethers, and pharmaceutical compositions containing them, are described. They have pharmaceutical activity, e.g. as anti-inflammatory agents.
