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Updated: Jul 24, 2026

Solid-phase Synthesis of [4.4] Spirocyclic Oximes
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Solid-phase Synthesis of [4.4] Spirocyclic Oximes

Published on: February 6, 2019

タンデム2コンポーネントエステル化によるサイクルエーサーのステレオセレクティブ構築:ビスムートトリブロミドの役割の解明

P Andrew Evans1, Jian Cui, Santosh J Gharpure

  • 1Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA. paevans@indiana.edu

Journal of the American Chemical Society
|September 18, 2003
PubMed
まとめ

この研究は,多くの医薬品の重要な成分であるテトラヒドロピランを合成するための新しい方法を紹介しています. 触媒的アプローチは,複雑な循環エーテルを構築するためのステレオ選択的経路を提供し,薬剤発見の努力を強化します.

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E2 Reaction: Stereochemistry and Regiochemistry02:43

E2 Reaction: Stereochemistry and Regiochemistry

Elimination reactions of alkyl halides can yield one or more alkenes depending on the specific regiochemical and stereochemical considerations. While the regiochemistry of the reaction governs the location of the double bond in the product, the stereochemical requirements often influence the geometry.
When a substrate with two different β hydrogens undergoes an E2 elimination, the presence of a strong base can yield two regioisomeric alkenes. The more-substituted alkene is the major product and...
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Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
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Hydroboration-Oxidation of Alkenes

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