Photoredox-catalyzed allylation of α-gem-difluorinated organohalides with allylsulfones proceeded smoothly under visible light irradiation to give 4,4-difluoroalkenes in good yields. In the presence of catalytic Ru(bpy)3Cl2, Hantzsch ester, and diisopropylethylamine, the reaction was complete within 2 h. Using the same methodology, three-component cascade reactions to give 6,6-difluoroalkenes were
A convenient route for the synthesis of difluoromethylene-functionalized compounds from chlorodifluoroacetic acid has been investigated. Bis(chlorodifluoroacetyl) peroxide, which was synthesized from chlorodifluoroacetic acid via its acid anhydride, was found to be a good reagent for the chlorodifluoromethylation of electron-rich aromatic compounds and olefins. The chlorine atom of the chlorodifluoromethylated
Chlorodifluoromethyl group was introduced into aromatic rings using bis(chlorodifluoroacetyl) peroxide which was readily prepared from corresponding acid anhydride with 30% hydrogen peroxide, and the chlorine was successively replaced by hydrogen or allyl group in excellent yields under radical conditions.
An object of the present invention is to provide a novel method for producing a fluorine-containing methylene compound. The above object can be achieved by a method for producing a compound represented by formula (1):
wherein R
1
represents an organic group, R
A
represents hydrogen or fluorine, R
4a
represents hydrogen or an organic group, R
4b
represents hydrogen or an organic group, R
5a
represents hydrogen or an organic group, R
5b
represents hydrogen or an organic group, and R
2
represents hydrogen or an organic group; R
2
is optionally connected to R
4a
to form a ring; the method comprising step A of reacting a compound represented by formula (2):
wherein X
1
represents a leaving group, and other symbols are as defined above, with a compound represented by formula (3):
wherein X
2
represents a leaving group, and other symbols are as defined above, in the presence of a reducing agent as desired, under light irradiation.