Efficient Utilization of Tetrabutylammonium Bifluoride in Halofluorination Reactions

Article abstract of DOI:10.1021/jo00279a013

The halofluorination reaction of a variety of alkenes by using tetrabutylammonium bifluoride (TBABF) in the presence of N-halosuccinimide is described.This process occurs stereospecifically to afford anti addition products, and with unsymmetrical olefins a marked Markovnikov-type regioselectivity is observed.In some cases, formation of a remarkable amount of the corresponding dihalo derivatives was found, but this undesirable side reaction can be avoided by using N-iodosucciniumide (NIS) as halogenating agent.If N-bromosuccinimide (NBS) or N-chlorosuccinimide (NCS) is utilized, these dihalo compounds can be easily removed from the halofluorinated compounds by simple column chromatography on silica gel.A mechanism for this side reaction is postulated.