二次氨基酸与Cu (I) /酸-尿素催化剂组合反应的二次氨基酸的酶选择性A(3) 反应
1Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States.
Journal of the American Chemical Society
|April 4, 2015
概括
这项研究引入了一种高效的铜催化不对称A(3) 反应,用于从pyrrolidines合成propargylamines. 该方法实现了高的enantioselectivity,并允许随后的转化为enantiopure.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 合反应 (A(3) 是合成甲胺的一个有价值的方法.
- 在有机合成中,开发高效和选性催化系统用于A(3) 反应仍然是有机合成的一个关键挑战.
研究的目的:
- 开发一种新型的铜催化不对称A(3) 反应,使用pyrrolidine和相关氨基.
- 为了在甲胺的合成中实现高的反选择性.
- 为了探索合成的propargylamines转化为allenes.
主要方法:
- 不对称的A(3) 反应使用铜 (CuI) 作为催化剂.
- 使用含有碳酸和氨酸组的双功能共催化剂.
- 反应条件的优化,包括催化剂负荷和温度.
- 随后的转化由propargylamines到allenes.
主要成果:
- 甲胺被合成时具有很高的反体过量 (高达96%).
- 低催化剂负载 (低至1mol%) 是有效的.
- 罗利丁衍生的基胺被转化为基,而不会损失其反纯度.
结论:
- 一种新且高效的铜催化不对称A(3) 反应已经确立.
- 开发的方法可以获得高度纯净的propargylamines和allenes.
- 双功能共催化剂在实现高反选择性方面发挥着至关重要的作用.
相关概念视频
Preparation of 1° Amines: Azide Synthesis
4.9K
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...
4.9K
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
3.9K
In the presence of an aqueous base and a halogen, primary amides can lose the carbonyl (as carbon dioxide) and undergo rearrangement to form primary amines. This reaction, called the Hofmann rearrangement, can produce primary amines (aryl and alkyl) in high yields without contamination by secondary and tertiary amines.
3.9K
Acid Halides to Amides: Aminolysis
4.8K
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...
4.8K
Preparation of Amines: Alkylation of Ammonia and Amines
5.1K
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...
5.1K
Preparation of Amines: Reductive Amination of Aldehydes and Ketones
4.3K
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.
4.3K
Amines to Sulfonamides: The Hinsberg Test
4.7K
The Hinsberg test is a method to identify primary, secondary and tertiary amines, named after its pioneer, Oscar Hinsberg. Here, amines are treated with benzenesulfonyl chloride, also known as the Hinsberg reagent, in the presence of an excess of aqueous base, followed by acidification. Based on the nature of the amines, different changes are observed.
Generally, a primary amine reacts with the Hinsberg reagent to produce an N-substituted benzenesulfonamide. The electron-withdrawing sulfonyl...
Generally, a primary amine reacts with the Hinsberg reagent to produce an N-substituted benzenesulfonamide. The electron-withdrawing sulfonyl...
4.7K


