of unactivated alkylbromides and iodides. Reactions of alkyl iodides with TMSCF2H were mediated by a copper catalyst using CsF as the activator, while reactions of less reactive alkylbromides required a combination of palladium and a stoichiometric amount of CuI as the catalysts. Preliminary mechanistic studies of the synergistic Pd/Cu-catalyzed difluoromethylation of alkylbromides suggest that it
Hydrochlorofluoromethylation of unactivated alkenes with chlorofluoroacetic acid
作者:Claudio F. Meyer、Sandrine M. Hell、Jeroen B.I. Sap、Antonio Misale、Aldo Peschiulli、Daniel Oehlrich、Andrés A. Trabanco、Véronique Gouverneur
DOI:10.1016/j.tet.2019.130679
日期:2019.11
An operationally simple method enabling hydrochlorofluoromethylation of unactivated alkenes under visible light activation is reported. The procedure has various benefits. It uses commercially available and inexpensive chlorofluoroacetic acid and phenyliodine(III) diacetate for the generation of the required chlorofluoromethyl radical, it converts feedstock olefins into attractive 1-chloro-1-fluoroalkanes
Hydrodifluoromethylation of Alkenes with Difluoroacetic Acid
作者:Claudio F. Meyer、Sandrine M. Hell、Antonio Misale、Andrés A. Trabanco、Véronique Gouverneur
DOI:10.1002/anie.201903801
日期:2019.6.24
hydrodifluoromethylation of alkenes is reported using difluoroacetic acid and phenyliodine(III) diacetate in tetrahydrofuran undervisible‐light activation. This metal‐free approach stands out as it uses inexpensive reagents, does not require a photocatalyst, and displays broad functional group tolerance. The procedure is also operationally simple and scalable, and provides access in one step to high‐value
Fluoride ion-mediated nucleophilic fluoroalkylation of alkyl halides with Me3SiCF2SPh: Synthesis of PhSCF2- and CF2H-containing compounds
作者:Ya Li、Jinbo Hu
DOI:10.1016/j.jfluchem.2008.01.010
日期:2008.5
A facile and highly efficient nucleophilic (phenylthio)difluoromethylation of alkylhalides has been achieved via fluoride ion-mediated substitution reaction using [difluoro(phenylthio)methyl]trimethylsilane (Me3SiCF2SPh). The reaction proceeds well with primary alkyl bromides (or alkyl iodides) in DME solvent when CsF/15-crown-5 was used as the fluoride source/additive. The PhSCF2-containing products
Nucleophilic substitution reactions of difluorormethyl phenyl sulfone with alkyl halides leading to the facile synthesis of terminal 1,1-difluoro-1-alkenes and difluoromethylalkanes
申请人:Prakash Surya G. K.
公开号:US20060052643A1
公开(公告)日:2006-03-09
(Benzenesulfonyl)difluoromethyl anion, in situ generated from difluoromethyl phenyl sulfone and a base, was found to easily undergo nucleophilic substitution reactions (S
N
2) with primary alkyl halides, elemental halogens, and perfluoroalkyl halides with good selectivity. The formed (benzenesufonyl)difluoromethylalkanes are useful intermediates for the facile preparation of 1,1-difluoro-1-alkenes and difluorometbylalkanes. Thus, difluoromethyl phenyl sulfone acts as both “CF
2
═” and “CF
2
H
−
” synthons.