オレフィンと機能化されたヒドロキシラミンとの鉄 (((II)) 触媒による分子内アミノヒドロキシル化
Guan-Sai Liu1, Yong-Qiang Zhang, Yong-An Yuan
1Department of Chemistry, Georgia State University, 100 Piedmont Avenue SE, Atlanta, Georgia 30303, United States.
Journal of the American Chemical Society
|February 14, 2013
まとめ
新しい鉄 (((II) 触媒は,オレフィンの効率的なダイアステロ選択性アミノヒドロキシル化を可能にします. このプロセスは,高い選択性を持つ有価なアミノアルコールを生成し,リガンドと対アニオン選択による制御を提供します.
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
- 合成方法論 合成方法論
背景:
- アミノヒドロキシル化は,アミノアルコールを合成するための重要な変換です.
- 効率的で選択的な触媒方法の開発は依然として課題です.
研究 の 目的:
- オレフィンのダイアステロセレクティブアミノヒドロキシル化のための新しい鉄 (II) 触媒を開発する.
- この変換におけるメカニズムと制御選択性を調査する.
主な方法:
- 機能化されたヒドロキシラミンを含む新しい鉄 (II) 複合体を用いた触媒.
- キラル鉄 (((II)) コンプレックスを使用した非対称な触媒.
- 予備的なメカニズム研究.
主要な成果:
- オレフィンの効率的な分子内アミノヒドロキシル化が達成されました.
- 高いダイアステレオ選択性 (最大> 20:1) が観察されました.
- アミノヒドロキシル化またはアジリジル化を行うことができる鉄ナイトレノイド中間物質が提案されました.
結論:
- 新しい鉄 (((II) 複合体は,ダイアステロ選択性アミノヒドロキシル化の効果的な触媒である.
- 選択性は,カウンターアニオンとリガンドの組み合わせを変更することによって調整できます.
- この発見は,合成的に有用なアミノアルコールへの新しい経路を提供する.
関連する概念動画
Amines to Alkenes: Hofmann Elimination
Alkenes can be obtained from amines via an E2 elimination. The amine is first converted into a good leaving group, such as a quaternary ammonium salt. This is accomplished by treating the amine with an excess of alkyl halide, which results in a halide salt. Next, the halide salt is transformed into a hydroxide salt that functions as a base to enable elimination.
Under thermal conditions, the hydroxide can abstract a proton from the β carbon; this generates an alkene with the simultaneous...
Under thermal conditions, the hydroxide can abstract a proton from the β carbon; this generates an alkene with the simultaneous...
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Introduction
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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.
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Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
Amines to Amides: Acylation of Amines
Various carboxylic acid derivatives (such as acid chlorides, esters, and anhydrides) can be used for the acylation of amines to yield amides. The reaction requires two equivalents of amines. The first amine molecule functions as a nucleophile and attacks the carbonyl carbon to produce a tetrahedral intermediate. This is followed by the loss of the leaving group and restoration of the C=O bond.
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...
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Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview
Primary amines react with carbonyl compounds—aldehydes and ketones—to generate imines. Imines consist of a C=N double bond and are named Schiff bases after its discoverer—the German chemist Hugo Schiff. On the other hand, secondary amines react with carbonyl compounds to give enamines. In enamines, the presence of a C=C double bond adjacent to the nitrogen atom leads to the delocalization of the lone pair.
Acid 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...


