Boron Trifluoride Promoted Reaction of Alkyl Hypohalites with Alkenes. A New Synthesis of Fluoro Halides

Article abstract of DOI:10.1021/jo00167a011

The reactions of the following alkenes with alkyl hypohalites and boron trifluoride (BF3) were investigated: cyclohexene (3), 1-hexene (8), trans-1,2-dichloroethylene (15), methyl acrylate (18), methyl crotonate (25), methyl isocrotonate (29), butadiene (33), methyl vinyl ketone (42), and styrene (45).Reactions of these alkenes with methyl hypochlorite (1) and BF3 in dichloromethane give fluoro chloride adducts as well as methoxy chlorides with the percentage of fluoro chlorides varying from 75percent for 29 to 8percent for 45.Fluoro bromide adducts are obtained with methyl hypobromite (2).Reactions with the tert-butyl hypohalites and BF3 also give fluoride incorporation.The percentage of fluoride incorporation with 1 or 2 is significantly greater in carbon tetrachloride than in dichloromethane.