Related Experiment Video
Updated: Sep 7, 2025

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Photocatalyzed Defluorinative Dichloromethylation of α-CF3 Alkenes Using CHCl3 as the Radical Source
Mei-Chun Wu1,2, Yi-Xuan Chen1, Ming-Zhi Li1
1College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China.
Abstract:
A visible-light-induced defluorinative dichloromethylation of α-CF3 alkenes was developed with cheap and readily accessible chloroform simultaneously as a dichloromethylation reagent and reaction medium, leading to the facile preparation of new polyhalogenated scaffolds. Notably, the change from CHCl3 to CDCl3 offers a straightforward pathway for accessing the deuterated analogues with excellent degrees of D incorporation. Mechanistic studies suggested the reaction underwent a radical addition of the dichloromethyl radical with alkenes, followed by sequential single-electron transfer and defluorination. This protocol features mild conditions, easy operation, facile scalability, and high efficiency, allowing convenient access to dichloronated gem-difluoroalkenes.
More Related Videos
10:10Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
Published on: July 28, 2018
09:12[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Related Concept Videos
Radical Substitution: Halogenation of Alkanes and Alkyl Substituents
In the initiation step of the reaction, the chlorine molecule undergoes homolytic cleavage in the presence of light or heat, forming two highly reactive chlorine radicals. Propagation occurs in two...
Radical Substitution: Allylic Chlorination
Halogenation of Alkenes
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.
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Acid-Catalyzed α-Halogenation of Aldehydes and Ketones
In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
Base-Promoted α-Halogenation of Aldehydes and Ketones