Herein, we report anew strategy for carbon À carbon bond scission and intramolecular ring expansion fluorination of unactivated cyclopropanes,w hichw as accomplished with an ew hypervalent fluoroiodane(III) reagent 1.T his novel method delivers medicinally relevant 4-fully substituted fluoropiperidines in moderate to high yields with excellent regioand diastereoselectivity.Reagent 1,which has an N-acetylbenziodazole framework, was readily synthesized via three steps in 76 %o verall yield and was characterized by NMR spectroscopya nd X-ray crystallography.O wing to the presence of as econdary I•••O bonding interaction between the l 3 -iodane atom and the carbonyl oxygen of the acetyl group of the Nacetylbenziodazole framework, 1 has excellent stability and can be stored at ambient temperature for 6months without any detectable decomposition. Density functional theory calculations and experimental studies showed that the reaction proceeds via acarbocation intermediate that readily combines with afluoride ion to generate the product.

The development of convenient new methods for the synthesis of organic azides is highly desirable. Herein, we report a practical method for dehydroxyazidation of alcohols via an S N 2 pathway involving PPh 3 and trifunctional benziodazolone-based hypervalent azido-iodine(III) reagents, which function as an electrophilic center, an azido source, and a base. This mild, chemoselective method was used for latestage azidation of structurally complex alcohols, as well as for a new synthetic route to the antiepileptic drug rufinamide. The reaction mechanism was also investigated both experimentally and computationally.

Nowadays, hypervalent iodine chemistry has remarkably advanced in parallel with the emergence of novel hypervalent iodine reagents. Hypervalent iodine reagents, due to their outstanding characteristics including rich reactivities, excellent chemoselectivity, stability, and environmental friendliness, are becoming more and more popular in the synthetic organic chemistry. In this Account, a number of recent elegant research works and our perspective on the future of hypervalent iodine chemistry is presented.1 Introduction2 Recent Advances and Discussion2.1 Novel Reactivities of Hypervalent Iodine Reagents2.2 Atom-Economical Reactions Promoted by Hypervalent Iodine Reagents2.3 Other Applications of Hypervalent Iodine Reagents2.4 The Applications of DFT Calculations in Elucidating Reaction Mechanism Involving Hypervalent Iodine Reagents3 Outlook and Conclusion

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Direct dehydroxytrifluoromethylthiolation of alcohols is an attractive strategy for accessing CF 3 S-containing compounds. Herein, we report a method for dehydroxytrifluoromethylthiolation of alcohols by using the combination of hypervalent iodine(III) reagent TFTI and N-heterocyclic carbenes. This method shows excellent stereospecificity and chemoselectivity to give a product with clean inversion of the configuration of hydroxyl groups as well as can be used for late-stage modification of structurally complex alcohols. The reaction mechanism is proposed with experimental and computational evidence.