パラジウム触媒によるメチル硫酸化物とアリルハリドの直接アリレーション
Tiezheng Jia1, Ana Bellomo, Kawtar E L Baina
1Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, USA.
Journal of the American Chemical Society
|February 20, 2013
まとめ
パラジウム触媒による新しい方法により,硫黄酸化物のα-アリレーションが可能になった. このアプローチは,生物活性化合物を合成するために,ジメチル硫酸化物やアリル塩化物などの困難な基質を含む,様々な硫酸化物とアリルハリドを効率的に結合します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 合成方法論 合成方法論
背景:
- 硫酸化物は弱酸性アルファ陽子を有しており,機能化することが困難である.
- 硫黄酸化物におけるC-S結合形成の効率的な方法の開発は,複雑な分子を合成するために極めて重要です.
研究 の 目的:
- 活性化されていない硫黄酸化物の直接α-アリレーションのための新しいパラジウム触媒法を開発する.
- サルフォキシドアリレーションの範囲を,挑戦的な基板とコップリングパートナーを含むように拡大する.
主な方法:
- α-アリレーション反応を触媒化するために,パラジウムフォスフィン複合体を利用した.
- スルフォキシドα-プロトンの可逆性デプロトネーションのために使用されたリチウム三酸化物 (LiOtBu).
- アリルブロミド,アリル塩化物,アルキルメチル硫酸化物の広い範囲に対応するために最適化された反応条件.
主要な成果:
- 様々なアリルメチル硫酸化物とアリルブロミドのパラジア触媒によるα-アリレーションが成功しました.
- アルキルメチル硫酸化物 (例えばジメチル硫酸化物) とアリル塩化物を含む,より困難な基板での方法の有効性を実証しました.
- 潜在的な生物学的活性を持つベンジル硫酸化物の中間物質を合成した.
結論:
- 開発されたパラジウム触媒法では,活性化されていないスルフォキシドのα-アリレーションのための汎用的かつ効率的な経路を提供します.
- この方法論は,有機合成における硫黄酸化物の合成用途を拡大する.
- このアプローチは,生物活性硫黄酸化物誘導体の製造に有用である.
関連する概念動画
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In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
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Introduction
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