相关实验视频
Updated: Sep 19, 2025

09:58
Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
11.8K
条件调节的区域差异转移使用甲醇作为可持续的H氧化物化
Ishani Borthakur1, Srabani Nandi1, Isha Garg2
1Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, 208016, India.
ChemSusChem
|June 4, 2025
概括
这项研究提出了一种新的方法,用于使用甲醇作为源的环氧化物进行区域分离转移化. 反应条件,而不是催化剂,控制区域选择性,使选择性环氧化物功能化.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 可持续化学 可持续化学
背景情况:
- 氧化物减少对于有机合成至关重要.
- 甲醇作为源面临诸如甲氧化等挑战.
- 选择性环氧化物功能化需要受控的减少.
研究的目的:
- 使用甲醇开发一种不同区域的环氧化物转移化方法.
- 通过单一的催化剂调节反应条件来控制区域选择性.
- 扩展一合成的方法.
主要方法:
- 使用单一的 (((III) 催化剂进行环氧转移化.
- 使用甲醇作为可持续的源.
- 操纵反应条件 (如KOTf,TFE,KOH,tAmOH等添加剂) 来控制区域选择性.
主要成果:
- 实现了史无前例的环氧化物的 regiodivergent 转移化.
- 证明了KOTf/TFE的抗马尔科夫尼科夫选择性和KOH/tAmOH的马尔科夫尼科夫选择性.
- 成功地将该方法扩展到酒精的单β甲基化.
结论:
- 反应条件的战略调制使选择性环氧化物功能化成为可能.
- 开发的方法为有机合成提供了一种可持续和多用途的方法.
- 机理学研究阐明了支配区域选择性的因素.
相关概念视频
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.4K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.4K
Reduction of Alkenes: Catalytic Hydrogenation
12.6K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.6K
Hydroboration-Oxidation of Alkenes
9.0K
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
9.0K
Preparation of Epoxides
8.1K
Overview
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of...
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of...
8.1K
Regioselectivity and Stereochemistry of Hydroboration
8.4K
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn...
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn...
8.4K
Regioselectivity of Electrophilic Additions-Peroxide Effect
8.9K
In the presence of organic peroxides, the addition of hydrogen bromide to an alkene yields the isomer that is not predicted by Markovnikov’s rule. For example, the addition of hydrogen bromide to 2-methylpropene in the presence of peroxides gives 1-bromo-2-methylpropane. This addition reaction proceeds via a free radical mechanism, which reverses the regioselectivity. The free radical reaction mechanism involves three stages: initiation, propagation, and termination.
8.9K

