通过化酸复合物合成富含的基化物
Christopher Sandford1, Ramesh Rasappan1, Varinder K Aggarwal1
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|August 6, 2015
概括
使用酸盐复合物和Selectfluor II有效地转化为二次酸. 这种方法实现了高化特异性,对于合成纯化化合物至关重要.
科学领域:
- 有机化学
- 化化学
- 立体选择合成
背景情况:
- 基化物是制药和农业化学品的重要组成部分.
- 开发高效和刻板选择的合成方法仍然是一个挑战.
研究的目的:
- 报告一种用于将性二次乙烯转化为基化物的新方法.
- 调查酸盐复合物的使用在电友化中作为核.
主要方法:
- 使用酸盐复合物,由酸和PhLi生成,作为核爱物.
- 使用 Selectfluor II作为电友的化剂.
- 研究了烯作为激素陷的作用,以增强对抗特异性.
主要成果:
- 实现了性二次乙烯转化为基化物.
- 在化过程中被证明反应时间短.
- 在广泛的基质中观察到几乎完全的酶特异性.
结论:
- 开发的方法提供了一条有效的途径,以化丰富.
- 使用酸盐复合物和Selectfluor II为立体选择性化提供了有价值的工具.
- 捕捉基因对改善反应的立体化学结果有好处.
相关概念视频
Hydroboration-Oxidation of Alkenes
12.4K
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.
12.4K
Alkylation of β-Ketoester Enolates: Acetoacetic Ester Synthesis
4.9K
Acetoacetic ester synthesis is a method to obtain ketones from alkyl halides and β-keto esters. The reaction occurs in the presence of an alkoxide base that abstracts the acidic proton of the β-keto esters. The step results in an enolate ion which is doubly stabilized. The enolate then reacts with an alkyl halide via the SN2 process to produce an alkylated ester intermediate with a new C–C bond. The hydrolysis of the intermediate, followed by acidification, results in an...
4.9K
Regioselectivity and Stereochemistry of Hydroboration
9.8K
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 stereochemistry.
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 stereochemistry.
9.8K
Alkylation of β-Diester Enolates: Malonic Ester Synthesis
4.4K
Malonic ester synthesis is a method to obtain α substituted carboxylic acids from ꞵ-diesters such as diethyl malonate and alkyl halides.
4.4K
Halogenation of Alkenes
21.2K
Halogenation is the addition of chlorine or bromine across the double bond in an alkene to yield a vicinal dihalide. The reaction occurs in the presence of inert and non-nucleophilic solvents, such as methylene chloride, chloroform, or carbon tetrachloride.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
21.2K
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
8.0K
Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.
8.0K


