Alkyne hydroamination is an effective approach for the production of enamines and enamine‐containing N‐heterocycles. However, stereoselectivity control is a considerable challenge in this reaction because of the electronic repulsion between an incoming nitrogen lone pair and the alkyne π‐system. Herein, we propose a methodology involving β‐regio‐ and Z‐selective alkyne hydroamination by using tetrafluoro‐λ6‐sulfanyl (SF4) alkynes under superbasic, naked anion conditions. The reaction is compatible with a wide variety of N‐heterocycles, including indoles, carbazoles, pyrazoles, and imidazoles, and selectively furnishes SF4‐linked Z‐vinyl enamines with β‐regioselectively. Moreover, the method can be extended to the β‐ and Z‐controlled, base‐mediated alkyne hydrophenoxylation with phenols to provide SF4‐linked Z‐vinyl ethers in high yields. As the SF4 unit has attracted attention as a bioisostere for alkynes, p‐benzenes, bicyclo[1.1.1]pentyl (BCP) groups, and cubanes in medicinal chemistry, this chemistry represents an effective approach to creating novel drug candidates incorporating SF4‐containing molecules.

Herein, we report the metal-free hydration of pyridine-SF 4 -alkynes, under acidic conditions and with reaction durations ranging from 5 min to 10 h at room temperature, to synthesize pyridine-SF 4 -methyl ketones in yields of 59−93%. Further, we demonstrate the synthetic applications of the synthesized pyridine-SF 4 -methyl ketones, such as chlorination, NaBH 4 reduction, Baeyer− Villiger oxidation, and the generation of enol-triflates. These compounds hold promise as useful building blocks in the syntheses of a wide range of SF 4 -containing drug candidates.

The elemental sulfur-mediated synthesis of acyl fluorides from carboxylic acids is achieved using Selectfluor. A broad range of acyl fluorides are accessible from carboxylic acids while avoiding the formation of acid anhydrides. 19 F NMR spectra suggest that S 8 -fluorosulfonium cation A and neutral S 8 -difluoride A′ generated in situ are the reactive species in this deoxyfluorination reaction.Letter pubs.acs.org/OrgLett

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Alkyne hydroamination is an effective approach for the production of enamines and enaminecontaining N-heterocycles. However, stereoselectivity control is a considerable challenge in this reaction because of the electronic repulsion between an incoming nitrogen lone pair and the alkyne π-system. Herein, we propose a methodology involving β-regio-and Zselective alkyne hydroamination by using tetrafluoro-λ 6sulfanyl (SF 4 ) alkynes under superbasic, naked anion conditions. The reaction is compatible with a wide variety of N-heterocycles, including indoles, carbazoles, pyrazoles, and imidazoles, and selectively furnishes SF 4linked Z-vinyl enamines with β-regioselectively. Moreover, the method can be extended to the β-and Zcontrolled, base-mediated alkyne hydrophenoxylation with phenols to provide SF 4 -linked Z-vinyl ethers in high yields. As the SF 4 unit has attracted attention as a bioisostere for alkynes, p-benzenes, bicyclo[1.1.1]pentyl (BCP) groups, and cubanes in medicinal chemistry, this chemistry represents an effective approach to creating novel drug candidates incorporating SF 4 -containing molecules.