オレフィンのルテニウム触媒による効率的で地域選択的な水素アミノメチル化
Lipeng Wu1, Ivana Fleischer, Ralf Jackstell
1Leibniz-Institut für Katalyse e.V., an der Universität Rostock, Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
Journal of the American Chemical Society
|February 20, 2013
まとめ
新しいフォスフィノ-イミダゾール結合体を持つルテニウム触媒は,オレフィンとアミンを効率的に価値ある二次および三次アミンに変換します. この水素アミノメチル化反応は,多種多様な基板に対する高収量と優れた地域選択性を提供します.
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
- 有機金属化学 有機金属化学
背景:
- 水素アミノメチル化は,アミンを合成するための重要な反応です.
- 効率的で地域選択的な触媒システムの開発は依然として課題です.
研究 の 目的:
- オレフィンのルテニウム触媒による新しい水素アミノメチル化について報告する.
- 特定のリガンドと触媒を用いて,高収量と地域選択性を達成する.
主な方法:
- トリルテニウムドデカカルボニルを触媒前駆体として利用する.
- 特定の2フォスフィノ置換イミダゾールリガンドを使用しています.
- 様々なアリファティック・オレフィンと機能化されたオレフィンが,主および二次アミンと反応する.
主要な成果:
- 二次および三次アミンの場合,一般的に高い収量 (最大96%) を達成しました.
- 優れた地域選択性を示した (n/iso比率は99:1まで).
- 触媒システムは,単純なオレフィンと機能化されたオレフィンの両方に有効であることが証明されました.
結論:
- 開発されたルテニウム触媒による水素アミノメチル化は,効率的で地域選択的な方法である.
- 2フォスフィノ置換イミダゾールリガンドの使用は,反応の成功の鍵です.
- この方法は,簡単に入手可能な原料から多様なアミンを合成するための貴重な経路を提供します.
関連する概念動画
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
02:36Regioselectivity and Stereochemistry of Hydroboration
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
02:17Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
If a set of reactants can yield multiple constitutional isomers, but one of the isomers is obtained as the major product, the reaction is said to be regioselective. In such reactions, bond formation or breaking is favored at one reaction site over others.
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
01:25Radical Anti-Markovnikov Addition to Alkenes: Overview
The addition of hydrogen bromide to alkenes in the presence of hydroperoxides or peroxides proceeds via an anti-Markovnikov pathway and yields alkyl bromides.
01:13Olefin Metathesis Polymerization: Overview
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
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.