Beilstein J. Org. Chem.2014,10, 344–351, doi:10.3762/bjoc.10.32
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Conclusion: Similar to many other Wittig-type gem-difluoroolefination reactions in the presence of PPh3, the reaction of TMSCF2Cl with aldehydes and activated ketones is effective.
Keywords: (chlorodifluoromethyl)trimethylsilane; difluorocarbene; gem-difluoroolefin; organo-fluorine; Wittig reaction; ylide
yields. It should be mentioned that the aromatic aldehydes with substituents such as t-butylthio, methoxy, and bromo groups on the phenyl ring showed similar reactivity. Moreover, this approach is also amenable to enolizable aldehydes, for example, gem-difluoroolefin 2h could be obtained in 47% yield
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Graphical Abstract
Scheme 1:
Various procedures for the generation of difluoromethylene phosphonium ylide [19-25].