Construction of atropisomeric benzoxepinone-embedded styrenes via intramolecular [3+2] cycloaddition and catalytic
Yue Wang1, Xingfu Wei1, Aiqi Xue1
1State Key Laboratory of Fine Chemicals, Department of Pharmaceutical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China. bmwang@dlut.edu.cn.
Abstract:
We present an intramolecular [3+2] cycloaddition of innovative (E)-α-aryl enal derivatives with 4-aminopyrazolone hydrochlorides/3-aminooxindole hydrochlorides to afford an array of atropisomeric benzoxepinone-based styrenes fused to spiro[pyrrolidine-pyrazolone/oxindole] scaffolds, and kinetic resolutions of the racemic adducts were implemented by reacting with benzyl alcohols, giving the corresponding two types of axially chiral styrenes in enantioenriched form with high s-factor. In addition, product transformations such as oxidative dehydrogenation and cross-coupling reactions have been demonstrated.
Related Concept Videos
Cycloaddition Reactions: Overview
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
Preparation of Epoxides
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of...
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Cycloaddition Reactions: MO Requirements for Thermal Activation

![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
