Communication
ChemComm
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In summary, we have developed a straightforward synthesis
of previously undisclosed a,a-difluoromethyl thioamides via a
tactic based on the nucleophilic transfer of a difluoromethyl
carbanion equivalent to isothiocyanates. The treatment of the
commercially available and experimentally convenient reagent
TMSCHF2 with potassium tert-amylate allows the efficient
formation of the difluorinated nucleophile. Full chemocontrol
is uniformly manifested as indicated in the cases of challenging
isothiocyanates embodying chemical moieties susceptible
of nucleophilic attack. This high yielding methodology fully
preserves its effectiveness when applied to the synthesis
of a,a-difluoromethyl oxoamide using isocyanates as amide
precursors.
We thank the University of Vienna and the OEAD for
generous support. Dr R. Bartolotta is acknowledged for initial
contributions and D. Dobusch for HRMS data. R. D’O. thanks
the University of Basilicata for a visiting doctoral fellowship.
This paper is dedicated to Professor Marko Mihovilovic in the
occasion of his 50th birthday.
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Conflicts of interest
There are no conflicts to declare.
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