JoVE - Journal of Visualized Experiments
JoVE Visualize
Contact Us
このページは機械翻訳されています。他のページは英語で表示される場合があります。 View in English

カルコゲン結合活性化剤 [1.1.1]プロペラン:サイクロブチル挿入によるスピロ[3.3]ヘプタンの構成

  • 0School of Chemistry and Chemical Engineering, Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, Shandong University, Jinan 250100, P. R. China.
Journal of the American Chemical Society +

|

2025年12月5日

|

2025年12月5日

PubMedで要約を見る

まとめ

この要約は機械生成です。

カルコゲン結合触媒は,プロペランのC-C σ-結合を活性化します. この突破は,新しい反応経路であるスピロ[3.3]ヘプタンの効率的な合成を可能にします.

科学分野

  • 有機化学
  • カタリシス
  • 合成方法論

背景

  • カルコゲン結合触媒は 新しい合成プラットフォームです
  • カルコゲン結合によるC-C σ-結合の活性化は依然として課題である.
  • 移行金属を使用した以前の方法は, [1.1.1]プロペランの活性化には効果的ではなかった.

研究 の 目的

  • [1.1.1]プロペランにおけるC-C σ-結合の活性化について,カルコゲン結合を用いて調べる.
  • スピロ[3.3]ヘプタンを合成するための新しい方法の開発.
  • 既存の触媒システムの限界を克服する.

主な方法

  • [1.1.1]プロペランのC-C σ-結合を活性化するために,カルコゲン結合触媒を使用する.
  • サイクロブチル分子のサイクロプロペノンへの挿入を容易にする.
  • 二重触媒モードを含む反応メカニズムの調査.

主要な成果

  • [1.1.1]プロペランのC-C σ結合をカルコゲン結合によって成功的に活性化.
  • サイクロプロペノンへの挿入によるスピロ[3.3]ヘプタンの効率的な合成.
  • 高効率で,低触媒負荷 (2.5 mol %) と穏やかな温度 (0 °Cから室温) で数分で反応が完了します.

結論

  • カルコゲン結合は,以前は大きな障害であった強力なC-C σ-結合を効果的に活性化することができる.
  • この研究は,メイングループ触媒を用いたスピロ[3.3]ヘプタンの新合成経路を確立している.
  • 開発された方法は,プロペラン機能化のための伝統的な移行金属触媒に非常に効率的で穏やかな代替手段を提供します.

関連する概念動画

Halogenation of Alkenes 02:46

18.3K

Halogenation is the addition of chlorine or bromine across the double bond in an alkene to yield a vicinal dihalide. The reaction occurs in the presence of inert and non-nucleophilic solvents, such as methylene chloride, chloroform, or carbon tetrachloride.
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.

A...

Conformations of Cycloalkanes 02:29

14.0K

Adolf von Baeyer attempted to explain the instabilities of small and large cycloalkane rings using the concept of angle strain — the strain caused by the deviation of bond angles from the ideal 109.5° tetrahedral value for sp3  hybridized carbons. However, while cyclopropane and cyclobutane are strained, as expected from their highly compressed bond angles, cyclopentane is more strained than predicted, and cyclohexane is virtually strain-free. Hence, Baeyer’s theory that...

Formation of Halohydrin from Alkenes 02:41

14.6K

An alkene, such as propene, reacts with bromine in the presence of water to yield a halohydrin. Halohydrins contain a halogen and a hydroxyl group attached to adjacent carbons. When the halogen is bromine, it is called a bromohydrin, while a chlorohydrin has chlorine as the halogen.

Halohydrin formation commences when the π electrons of the alkene react with electrophilic bromine to form a bridged intermediate called a bromonium ion. Water, acting as a nucleophile, uses a lone pair of...

Electrophilic 1,2- and 1,4-Addition of X<sub>2</sub> to 1,3-Butadiene 01:14

3.4K

Electrophilic addition of halogens to alkenes proceeds via a cyclic halonium ion to form a 1,2-dihalide or a vicinal dihalide.

Conjugated dienes react with halogens in a similar manner. However, in addition to the 1,2-dihalide, they also form a 1,4-dihalide. The mechanism involves two steps.
First, a nucleophilic attack by one of the diene π bonds on the electrophilic center of the polarized halogen molecule forms a halonium ion intermediate. This is followed by a nucleophilic attack of the...

Prochirality 02:05

4.8K

The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...

Electrophilic Addition to Alkynes: Halogenation 02:38

9.9K

Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.

Reaction Mechanism
In the first step, a π...