水中のアンモニアを水溶性Cp*Ir-アミン複合体によって触媒化されたアルコールでマルチアルキル化
Ryoko Kawahara1, Ken-ichi Fujita, Ryohei Yamaguchi
1Graduate School of Human and Environmental Studies, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
Journal of the American Chemical Society
|October 12, 2010
まとめ
研究者は,アルコールと水性アンモニアから有機アミンを合成するための新しい触媒システムを開発しました. この効率的でリサイクル可能な方法は,アミンの生産のためのよりグリーンな代替案を提供します.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- 有機アミンを合成するための効率的かつ持続可能な方法の開発は,化学において極めて重要です.
- 伝統的な方法は,しばしば厳しい条件を伴うか,かなりの廃棄物を発生させる.
- これらの制約に対処するために,新しい触媒システムが必要である.
研究 の 目的:
- 新しい水溶性Cp*Ir-アミン複合体を合成する.
- 水性アンモニアを用いた有機アミンの合成のための高度に原子経済的な触媒システムを開発する.
- アミン合成のための実用的で環境に害のない方法論を実証する.
主な方法:
- 水溶性Cp*Ir-アミン複合体の合成,具体的には[Cp*Ir(NH(3)) ((3))) [I] ((2) である.
- 合成した触媒を用いて,水性アンモニアを主および二次アルコールでマルチアルキル化する.
- 触媒のリサイクリングは,その再利用性と持続的な活動を評価するために行われます.
- 1,5,9-ノンナントリオールからキノリジジンの一瓶合成.
主要な成果:
- 新しい水溶性および空気安定性Cp*Ir-アミン触媒の合成に成功しました.
- 様々な三次および二次アミンを合成するための高度な原子経済性のシステムの開発.
- 高アクティビティのメンテナンスで触媒のリサイクル可能性の実証.
- キノリジジディンの単瓶合成が成功し,システムの汎用性を示した.
結論:
- 開発されたCp*Ir-アミン触媒システムは,有機アミン合成の効率的かつ実用的な経路を提供します.
- 窒素源として水性アンモニア,アルコールをアルキル化剤として使用することは,環境に優しいアプローチです.
- この方法論は,多様な有機アミンの生産のための持続可能な代替案を提供します.
関連する概念動画
01:30Preparation of Amines: Alkylation of Ammonia and Amines
Alkylation is one of the methods used to prepare amines. Direct alkylation of ammonia or a primary amine with an alkyl halide gives polyalkylated amines along with a quaternary ammonium salt through successive SN2 reactions. This process of making the quaternary salt through the direct alkylation method is called exhaustive alkylation.
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
01:07Acid Halides to Amides: Aminolysis
Aminolysis is a nucleophilic acyl substitution reaction, where ammonia or amines act as nucleophiles to give the substitution product. Acid halides react with ammonia, primary amines, and secondary amines to yield primary, secondary, and tertiary amides, respectively.
In the first step of the aminolysis mechanism, the amine attacks the carbonyl carbon of the acyl chloride to form a tetrahedral intermediate. In the second step, the carbonyl group is re-formed with the elimination of a chloride...
In the first step of the aminolysis mechanism, the amine attacks the carbonyl carbon of the acyl chloride to form a tetrahedral intermediate. In the second step, the carbonyl group is re-formed with the elimination of a chloride...
01:23Aldehydes and Ketones with Amines: Imine Formation Mechanism
Imine formation involves the addition of carbonyl compounds to a primary amine. It begins with the generation of carbinolamine through a series of steps involving an initial nucleophilic attack and then several proton transfer reactions. The second part includes the elimination of water, as a leaving group, to give the imine.
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
01:28Preparation of 1° Amines: Gabriel Synthesis
Direct alkylation is not a suitable method for synthesizing amines because it produces polyalkylated products. Gabriel synthesis is the most preferred method to exclusively make primary amines. The method uses phthalimide, which contains a protected form of nitrogen that participates in alkylation only once to predominantly give primary amines.
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
01:14Aldehydes and Ketones with Amines: Enamine Formation Mechanism
Enamine formation involves the addition of carbonyl compounds to a secondary amine through a series of reactions. The mechanism begins with the generation of carbinolamine, a nucleophilic attack followed by several proton transfer reactions. The hydroxyl group of the carbinolamine is converted into water to make a better leaving group that can push the reaction forward by eliminating a water molecule. In enamine formation, the last step involves the abstraction of a proton from the α carbon to...
02:15Preparation of Alcohols via Addition Reactions
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...