AgN3 - 终端酸盐的催化化和机理研究
Shanshan Cao1, Qinghe Ji1, Huaizhi Li1
1Department of Chemistry, Northeast Normal University, Changchun 130024, China.
Journal of the American Chemical Society
|March 29, 2020
概括
银化物 (AgN3) 被确定为终端化物的活性催化剂,可在低催化剂负载下有效合成乙烯酸,并澄清反应机制.
科学领域:
- 有机化学
- 催化剂
- 合成方法
背景情况:
- 酸盐的化使酸乙烯可以获得,这在有机合成中至关重要.
- 之前使用碳酸银 (Ag2CO3) 的方法需要高的催化剂负荷,并且机制不清楚.
研究的目的:
- 确定终端基的白银催化化中的活性催化物种.
- 开发一个更有效,更实用的催化系统.
- 为了阐明反应机制.
主要方法:
- 进行X射线衍射研究以确定催化物种.
- 银化物 (AgN3) 催化反应的开发和测试.
- 实验调查和理论计算.
主要成果:
- 银化物 (AgN3) 被确定为真正的催化物.
- 开发了一种高效的AgN3催化化终端基.
- 催化剂负荷降至5mol%,在50mmol尺度下具有高效率.
- 通过六个成员的过渡状态进行协调的添加机制比银乙机制更受青.
结论:
- 银酸是酸化的一个强大而有效的催化剂.
- 开发的方法提供了对乙烯酸合成的实用方法.
- 反应通过协调的加法机制进行,与之前的假设不同.
相关概念视频
Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
20.4K
Introduction
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.
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.
20.4K
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
8.8K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
8.8K
Alkynes to Aldehydes and Ketones: Acid-Catalyzed Hydration
10.4K
Introduction
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
10.4K
Preparation of 1° Amines: Azide Synthesis
4.5K
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...
4.5K
Preparation of Alkynes: Alkylation Reaction
11.8K
Introduction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
11.8K
Preparation of Alkynes: Dehydrohalogenation
17.7K
Introduction
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
17.7K


