末端オレフィンからの一次アルコール:トリプルリレー触媒による正式なアンチ・マルコヴニコフ水分化
Guangbin Dong1, Peili Teo, Zachary K Wickens
1Arnold and Mabel Beckman Laboratories for Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|September 17, 2011
まとめ
研究者らは,マルコフニコフのオレフィンの直接水分化のための新しいトリプルリレー触媒システムを開発しました. この方法では,アリル置換末端オレフィンを水を使用した原発アルコールに効率的に変換し,良好な収量が得られます.
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
- 合成化学 合成化学とは
背景:
- アルコール合成は,化学および製薬部門にとって不可欠です.
- オレフィンから原発アルコールへの直接的なアンチ・マルコヴニコフ的水分化は,難しいが価値のある変換です.
- 現在の方法,例えば水溶解/酸化は,ステキオメトリック反応剤を必要とし,間接的である.
研究 の 目的:
- アンチ・マルコヴニコフのオレフィン水素化のためのより直接的かつ効率的な方法を開発する.
- 初次アルコールの合成のために新しいトリプルリレー触媒システムを利用する.
主な方法:
- パラジウム触媒による酸化,酸触媒による水解,ルテニウム触媒による還元を統合したトリプルリレー触媒系が採用された.
- このシステムは,アリル置換末端オレフィンの間の水の純反応を容易にする.
主要な成果:
- この新しい触媒システムは,アリル置換末端オレフィンを原発アルコールに成功裏に変換した.
- 反応は良好な収穫量と優れた地域選択性で進行した.
- これは,既存の方法論と比較して,より直接的なアプローチを表しています.
結論:
- アンチ・マルコヴニコフ・オレフィン水素化のための直接的触媒方法が達成されました.
- トリプルリレーの触媒システムは,オレフィンから原発アルコールへの実用的で効率的な経路を提供します.
- この進歩は,アルコールの合成における工業的な応用のための大きな可能性を秘めています.
関連する概念動画
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Overview
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
02:35Acid-Catalyzed Dehydration of Alcohols to Alkenes
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02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
03:08Hydroboration-Oxidation of Alkenes
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
02:40Alkynes to Aldehydes and Ketones: Acid-Catalyzed Hydration
Introduction
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
01:33Preparation of Aldehydes and Ketones from Alcohols, Alkenes, and Alkynes
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