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Updated: Jun 6, 2025

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
10:10

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Published on: July 28, 2018

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通过电友激活,对基酸盐进行晚期 (放射性) 化

Kaiqiang Zhang1,2,3, Wanru Feng1,2,3, Zhaobiao Mou1,2,3

  • 1State Key Laboratory of Vaccines for Infectious Diseases, Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen, Fujian, China.

Nature communications
|November 28, 2024
PubMed
概括

研究人员开发了一种新方法,通过激活基酸盐来合成酸,这对于药物开发至关重要. 这一突破使得各种化合物的高效后期化成为可能,包括用于医学成像的放射追踪剂.

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Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives08:43

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

Published on: January 19, 2016

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Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts09:58

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts

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相关概念视频

Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene01:13

Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene

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.
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Electrophilic Addition to Alkynes: Halogenation02:38

Electrophilic Addition to Alkynes: Halogenation

Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
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Hydroboration-Oxidation of Alkenes03:08

Hydroboration-Oxidation of Alkenes

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.
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ortho–para-Directing Deactivators: Halogens01:24

ortho–para-Directing Deactivators: Halogens

Halogens are ortho–para directors. They are more electronegative than carbon. Therefore, as ring substituents, they can withdraw electrons through the inductive effect and deactivate the aromatic ring towards electrophilic substitution. Halogens also have an electron-donating resonance effect on the ring, which influences the orientation of the incoming electrophile. If an electrophile attacks at the ortho or the para position, the halogen donates electrons and stabilizes the intermediate...
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Electrophilic Addition to Alkynes: Hydrohalogenation02:35

Electrophilic Addition to Alkynes: Hydrohalogenation

Electrophilic addition of hydrogen halides, HX (X = Cl, Br or I) to alkenes forms alkyl halides as per Markovnikov's rule, where the hydrogen gets added to the less substituted carbon of the double bond. Hydrohalogenation of alkynes takes place in a similar manner, with the first addition of HX forming a vinyl halide and the second giving a geminal dihalide.
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α-Bromination of Carboxylic Acids: Hell–Volhard–Zelinski Reaction01:15

α-Bromination of Carboxylic Acids: Hell–Volhard–Zelinski Reaction

The method to achieve α-brominated carboxylic acids using a mixture of phosphorus tribromide and bromine is known as the Hell–Volhard–Zelinski reaction. The reaction is catalyzed by phosphorus tribromide, which can be used directly or produced in situ from red phosphorus and bromine. The mechanism comprises PBr3 catalyzed conversion of acid to acid bromide and hydrogen bromide. The acid bromide enolizes to its enol form in the presence of HBr. The nucleophilic enol attacks the...
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