Bessard, YvesMueller, UlrichSchlosser, Manfred2006-03-032006-03-032006-03-03199010.1016/S0040-4020(01)87828-5https://infoscience.epfl.ch/handle/20.500.14299/226859By treatment with Br2CF2 and Ph3P, 4 unfunctionalized olefins, 4 enol ethers and 1 bis-enol ether were converted to gem-difluorocyclopropanes. Thus, RCH:CHOPr (R = H, Me) gave difluorocyclopanes I in 73 and 83% yield, resp. The yields were considerably increased and isomerizations at the double bonds were avoided if the reactions were carried out in the presence of a macrocyclic polyether such as 18-crown-6 and a moderate excess of reagents. [on SciFinder (R)]Alkenes; Enols Role: RCT (Reactant)RACT (Reactant or reagent) (cyclopropanation ofwith dibromodifluoromethanedifluorocyclopropanes from); Ring closure and formation (cyclopropanationof alkenes and enols with dibromodifluoromethane)bromofluoromethane cyclopropanation alkenol alkene; cyclopropane difluoro geminal; fluorocyclopropanetext::journal::journal article::research article