Halide Sedef Karaman , Hamdullah Kılıç , Engin Şahin
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引用次数: 3
Abstract
The homogeneous asymmetric epoxidation of a range of enones was carried out using cumyl hydroperoxide, diethylzinc, and chiral pyrrolidinyl alcohol-containing ligands to afford the corresponding epoxy ketones with enantioselectivities of ≤97% ee. Examination of the enantioselectivities obtained in the asymmetric epoxidation of enones using a range of chiral ligands indicated that synergy between the sterically bulky bicyclo[2.2.2]octane skeleton and the substituents attached to the carbinol moiety played an important role in determining the reaction enantioselectivity. The position and nature of the substituent on the aromatic ring of the enone also had a pronounced effect on the observed enantioselectivity.
期刊介绍:
Cessation. Tetrahedron: Asymmetry presents experimental or theoretical research results of outstanding significance and timeliness on asymmetry in organic, inorganic, organometallic and physical chemistry, as well as its application to related disciplines, especially bio-organic chemistry.
The journal publishes critical reviews, original research articles and preliminary communications dealing with all aspects of the chemical, physical and theoretical properties of non-racemic organic and inorganic materials and processes. Topics relevant to the journal include: the physico-chemical and biological properties of enantiomers; strategies and methodologies of asymmetric synthesis; resolution; chirality recognition and enhancement; analytical techniques for assessing enantiomeric purity and the unambiguous determination of absolute configuration; and molecular graphics and modelling methods for interpreting and predicting asymmetric phenomena. Papers describing the synthesis or properties of non-racemic molecules will be required to include a separate statement in the form of a Stereochemistry Abstract, for publication in the same issue, of the criteria used for the assignment of configuration and enantiomeric purity.