置換された1,2-ダイアミン製剤の準備のための触媒C-Hアミネーション
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
Journal of the American Chemical Society
|August 6, 2008
まとめ
この研究では,硫酸塩酸エステルから新しいオキサチアジアジナンのヘテロサイクルを合成するためのロジウム触媒反応を導入しています. 軽度な還元により,貴重な1,2-ダイアミン産物が生み出され,C-N結合形成のための触媒的C-H機能化が示されます.
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
- 合成方法論 合成方法論
背景:
- 窒素を含むヘテロサイクルとダイアミンを構築するための効率的な方法の開発は,有機合成において極めて重要です.
- 触媒C-H機能化は,直接的な結合形成のための強力な戦略を提供し,機能化前のステップを最小限に抑えます.
- ハイドロキシアミン系硫酸エステルは,新しい変換のための多用途な出発材料です.
研究 の 目的:
- 新しいロジウム触媒によるC-H挿入反応を開発する.
- この方法を用いてユニークなオキサチアジアジナンのヘテロサイクルを合成する.
- 差異的に置換された1,2-ダイアミンの前駆体としてのこれらのヘテロサイクルの有用性を実証する.
主な方法:
- ヒドロキシラミン由来スルファメートエステルを使用したロジウム触媒C-H挿入反応.
- 合成されたヘテロサイクルを1,2-ダイアミン製品に変換するための軽い還元条件.
- 化学反応とダイアステロセレクティブ反応のモニタリングと製品の特徴付け.
主要な成果:
- ロジウム触媒によるC-H挿入によるユニークなオキサチアジアジナンのヘテロサイクルの合成が成功しました.
- ヘテロサイクルの軽度な還元により,異なる形で置換された1,2-ダイアミン産物の生成.
- 変異の全過程で,高いレベルの化学療法とダイアステロセレクティブ性が達成されました.
結論:
- ロジウム触媒によるC-H機能化は,オキサチアジアジナンのヘテロサイクルへの効果的な経路を提供します.
- これらのヘテロサイクルは,多様な1,2-ダイアミン構造にアクセスするための貴重な中間物質として機能します.
- 開発された方法論は,C-N結合の構築における触媒C-H活性化の可能性を強調しています.
関連する概念動画
01:22Preparation of 1° Amines: Azide Synthesis
Direct alkylation of ammonia produces polyalkylated amines, along with a quaternary ammonium salt. To exclusively prepare primary amines, the azide synthesis method can be used.
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
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...
01:38Preparation of Amines: Reductive Amination of Aldehydes and Ketones
Carbonyl compounds and primary amines undergo reductive amination first to produce imines, followed by secondary amines in the same reaction mixture, using selective reducing agents like sodium cyanoborohydride or sodium triacetoxyborohydride. Reductive amination produces different degrees of substitution of amines depending on the starting amine substrate.
01:13Preparation of Amines: Reduction of Amides and Nitriles
Nitriles can be reduced to primary amines using reducing agents like lithium aluminum hydride or catalytic hydrogenation. The reduction introduces an amino group with an extra carbon in the skeleton. Nitriles are formed from the reaction between alkyl halides and sodium cyanide through the SN2 mechanism. Primary alkyl halides are the preferred substrates to prepare nitriles.
Amides can be reduced to primary, secondary, and tertiary amines using catalytic hydrogenation, active metals like Fe,...
Amides can be reduced to primary, secondary, and tertiary amines using catalytic hydrogenation, active metals like Fe,...
01:20Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
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...
01:19Amines 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...
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...