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(21) Many of the methodologies in refs 15−17 have limited scope, use
harsh reaction conditions, or use superstoichiometric amounts of
reagent and a metal.
(22) NFSI and high energy light (254 nm) were required to achieve
decarboxylation.
(23) Fluorination was achieved with Selectfluor and either 254 nm
light or 350 nm light with acetone, although the substrate scope was very
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(24) It is still unclear whether radical fluorine transfer occurs directly
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generated derivative. For a representative recent proposal on the transfer
occurring from a radical anion of Selectfluor, see: Patel, N. R.; Flowers,
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(8) XeF2 is a crystalline solid that can readily be manipulated in air:
̌
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(25) This observation is also consistent with other literature reports of
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=
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(30) Higher equivalents of XeF2 did not further improve the reaction
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