The first ring-contraction monofluorination reaction mediated by a hypervalent iodine reagent is reported, and the use of the reaction for the synthesis of monofluorinated five-membered ring-fused oxazolines is described. By means of this reaction, a fluorine atom can be selectively introduced either on the five-membered ring or external to it, depending on whether or not the substrate has C-4 alkyl substituents. The reaction was used for the further conversion of probenecid and isoxepac.

中文翻译：

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高价碘介导的环收缩单氟化消除了单氟五元环稠合的恶唑啉

报道了由高价碘试剂介导的第一环收缩单氟化反应，并且描述了该反应在合成单氟化五元环稠合的恶唑啉中的用途。通过该反应，取决于底物是否具有C-4烷基取代基，可以将氟原子选择性地引入五元环上或其外部。该反应用于丙磺舒和异环己酮的进一步转化。