A stereocontrolled approach to electrophilic epoxides
作者:Otto Meth-Cohn、Clive Moore、Heinrich C. Taljaard
DOI:10.1039/p19880002663
日期:——
Lithium t-butyl hydroperoxide (easily generated by addition of an alkyl-lithium to anhydrous t-butyl hydroperoxide in THF solution) is a powerful reagent for the epoxidation of electrophilic alkenes at –20 to 0 °C under full stereocontrol.
in the yield of beta-diketone. On the other hand, the timing of proton transfer to the anionic intermediates is considered to be a key factor to yield the beta-hydroxy ketone. Information obtained from the photochemical study was useful to find the reaction conditions for the conversion of several aromatic epoxyketones to hydroxy ketones by the use of samarium diiodide. Addition of methanol significantly
Stereospecific Construction of Chiral Tertiary and Quaternary Carbon by Nucleophilic Cyclopropanation with Bis(iodozincio)methane
作者:Kenichi Nomura、Seijiro Matsubara
DOI:10.1002/asia.200900289
日期:2010.1.4
The reaction of a ketone having a leaving group at the α‐position, such as α,β‐epoxy ketone or α‐sulfonyloxy ketone, with bis(iodozincio)methane affords a zinc alkoxide of cyclopropanol. The reaction proceeds by nucleophilic addition of the dizinc to the carbonyl group and a sequential intramolecular nucleophilic substitution of the introduced iodozinciomethyl group to the adjacent electrophilic carbon
Dimethyl Sulfoxide Pivaloyl Chloride: A New Reagent for Oxidation of Alcohols to Carbonyls
作者:Abhishek Dubey、Subba Rao V. Kandula、Pradeep Kumar
DOI:10.1080/00397910701820343
日期:2008.2.13
Abstract An efficient procedure for conversion of alcohols to the corresponding carbonyl compounds, an alternative to the classical Swern oxidation, is described. Pivaloyl chloride is employed as a mild and inexpensive electrophile. A possible reaction mechanism is proposed.