アリルC−H結合のイリジウム催化シリレーション
1Department of Chemistry, University of California , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|December 17, 2014
まとめ
新しいイリジウム触媒法により,芳香性および異芳香性化合物のC-H結合のシリル化が可能になりました. このアプローチは,複雑な分子合成のための機能群の許容性と地域選択性を改善します.
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:
- アリルC-H結合の機能化は,複雑な有機分子の合成に不可欠です.
- ロジウム催化シリレーションのような以前の方法には,機能群の耐性および基板の適用範囲の制限があります.
- 効率的で選択的なC-Hシライレーションのための触媒システムの開発は,依然として活発な研究分野です.
研究 の 目的:
- アリルC−H結合のシル化のための新しいイリジウム触媒法を開発する.
- 新しい触媒システムの地域選択性と機能群耐性を調査する.
- シリアル化製品の有用性を,その後の化学的変換で実証する.
主な方法:
- イリジウム触媒 ([Ir(cod) ((OMe) ]2) をリガンドとして2,4,7-トリメチルフェナントロリンと組み合わせて使用した.
- シリアル化剤としてHSiMe (((OSiMe3) 2) を採用した.
- 様々なアレンとヘテロアレンとの反応を研究し,制限反応剤として芳香化合物を用いた.
主要な成果:
- アリルC-H結合のイリジウム触媒による効率的なシル化がアレンとヘテロアレンで達成された.
- シリレーション反応において,ステリカルに由来する高レベルの地域選択性を実証した.
- 以前のロジウム触媒法と比較して,機能群の耐性が著しく高かった.
- 酸化,ハロゲン化,クロスカップリングなどのさらなる変換のための結果のシリラーレン製品の適性を確認しました.
- 複雑な製薬化合物の後期機能化の方法を成功裏に適用しました.
結論:
- 開発されたイリジウム催化シリレーション法は,C-H機能化のための強力な新しいツールを提供します.
- この触媒システムは,強化された地域選択性と,多様なヘテロアレンを含むより広い基板範囲を提供します.
- このメソッドの高い機能群耐性と,後期段階の機能化への適用性は,薬剤化学と薬剤開発において価値あるものである.
さらに関連する動画
10:14Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
13.2K
09:37Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
10.3K
関連する概念動画
02:26Preparation and Reactions of Sulfides
6.1K
Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.
6.1K
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
9.8K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
9.8K
01:14Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
3.1K
Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The diazonio group in these salts can be easily displaced by different nucleophiles, yielding a wide variety of substituted benzenes. The leaving group departs as nitrogen gas, and this easy elimination is the driving force for the substitution reaction.
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo,...
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo,...
3.1K
01:20Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
2.7K
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...
2.7K
01:11Nucleophilic Aromatic Substitution: Elimination–Addition
5.8K
Simple aryl halides do not react with nucleophiles. However, nucleophilic aromatic substitutions can be forced under certain conditions, such as high temperatures or strong bases. The mechanism of substitution under such conditions involves the highly unstable and reactive benzyne intermediate. Benzyne contains equivalent carbon centers at both ends of the triple bond, each of which is equally susceptible to nucleophilic attack. This 50–50 distribution of products is...
5.8K
02:38Electrophilic Addition to Alkynes: Halogenation
10.7K
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.
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.
10.7K