A highly enantioselective asymmetric Darzens reaction catalysed by proline based efficient organocatalysts for the synthesis of di- and tri-substituted epoxides
A new class of easily available and readily tunable proline based chiral organocatalysts was found to efficiently catalyse an unprecedented highly enantioselective asymmetric Darzens reaction of α-chloro ketones and substituted α-chloro ketones with various aldehydes, which directly produces optically active di- and tri-substituted chiral epoxides with higher product yields (up to 97 %) and excellent
Visible-Light-Driven Epoxyacylation and Hydroacylation of Olefins Using Methylene Blue/Persulfate System in Water
作者:Gabriela F. P. de Souza、Juliano A. Bonacin、Airton G. Salles
DOI:10.1021/acs.joc.8b01026
日期:2018.8.3
olefins in water using methylene blue as photoredox catalyst and persulfate as oxidant is reported. In this unprecedented unified approach, two different transformations are accomplished using only one set of reagents. The method has a broad scope spanning a range of aromatic and aliphatic aldehydes as well as conjugated and nonconjugated olefins to deliver ketones and epoxyketones from abundant and
1,1,2,2‐Tetrahydroperoxy‐1,2‐diphenylethane was used for the efficient and metal‐free epoxidation of various α,β‐unsaturated ketones, carried out under mild alkaline conditions at room temperature.
Facile epoxidation of α, β-unsaturated ketones with urea-2,2-dihydroperoxypropane as a new oxidant
作者:Kaveh Khosravi、Shirin Naserifar
DOI:10.1007/s13738-016-0980-1
日期:2017.2
AbstractVarious aromatic α, β-unsaturatedketones were successfully transformed into their corresponding epoxides using urea-2,2-dihydroperoxypropane as the oxygen source for the first time. The reactions were carried out under mild alkaline conditions at room temperature in high yields and short reaction times. Graphical Abstract
Facile epoxidation of α,β-unsaturated ketones with cyclohexylidenebishydroperoxide
作者:Kavitha Jakka、Jinyun Liu、Cong-Gui Zhao
DOI:10.1016/j.tetlet.2006.12.104
日期:2007.2
Cyclohexylidenebishydroperoxide was successfully used as the oxygen source for the oxidation of α,β-unsaturatedketones for the first time. The corresponding epoxides were obtained in excellent yields under the Weitz–Scheffer reaction conditions.