1397202-05-9Relevant articles and documents
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Renfrew,Cretcher
, p. 738 (1935)
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Diastereoselective Corey-Chaykovsky 9-epoxymethylation of cinchona alkaloids: Access to chiral scaffolds with diverse functionalities
Boratynski, Przemyslaw J.,Skarzewski, Jacek
, p. 4473 - 4482 (2013/06/27)
Reaction of dimethylsulfonium methylide with Cinchona alkaloid ketones proceeds with complete diastereoselectivity to give epoxides of 8,9-like configuration. The reaction of dimethylsulfoxonium methylide gives different isomers, albeit with lower (4:1) selectivity. α-Epimerization of the alkaloid ketones resulted in formation of two separable diasteromeric products. The configurations of the epoxides were elucidated on the basis of NMR data combined with DFT calculations. Models explaining observed selectivity are discussed. The epoxides were efficiently transformed to a number of derivatives through selective SN2-type ring-opening reactions with various nucleophiles, often without the need of additional purification steps.
A versatile cobalt(II)-Schiff base catalyzed oxidation of organic substrates with dioxygen: Scope and mechanism
Punniyamurthy,Bhatia, Beena,Reddy, M. Madhava,Maikap, Golak C.,Iqbal, Javed
, p. 7649 - 7670 (2007/10/03)
Cobalt(II) complex 1a-f derived from Schiff bases act as efficient catalysts during the oxidation of wide range of organic substrates(e.g. alkenes, alcohols, benzylic compounds and aliphatic hydrocarbons) with dioxygen in the presence of aliphatic aldehydes or ketones or ketoesters. EPR studies on 1a-f complexes suggest that the aliphatic carbonyl compounds promote the formation of a cobalt(II)-superoxo species responsible for the oxidation of organic compounds. These studies also demonstrate the role of ligands on cobalt in controlling the chemoselectivity of these oxidations. A plausible mechanistic rational is also provided for these oxidations.