In this study, 1,1-difluoroallenes underwent a regioselective [2+3] cycloaddition with nitrile oxides and imine oxides in the presence of a AuCl catalyst. ()-4-Alkylidene-5,5-difluoroisoxazolines and -isoxazolidines were obtained in regioselective and diastereoselective manners by employing aurated difluoroallylic cation intermediates. The synthesized 5,5-difluoroisoxazolines were readily aromatized through dehydrofluorination or allylic fluorine substitution to provide 5-fluoroisoxazoles.

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http://dx.doi.org/10.1021/acs.orglett.3c02879DOI Listing

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