Importance of a Fluorine Substituent for the Preparation of meta - and para -Pentafluoro-λ6 -sulfanyl-Substituted Pyridines

(Hetero)aryl-SVI Fluorides: Synthetic Development and Opportunities

(Hetero)arylsulfur compounds where the S atom is in the oxidation state VI represent a large percentage of the molecular functionalities present in organic chemistry. More specifically, (hetero)aryl‐S^VI fluorides have recently received enormous attention because of their potential as chemical biology probes, as a result of their reactivity in a simple, modular, and efficient manner. Whereas the synthesis and application of the level 1 fluorination at S^VI atoms (sulfonyl and sulfonimidoyl fluorides) have been widely studied and reviewed, the synthetic strategies towards higher levels of fluorination (levels 2 to 5) are somewhat more limited. This Minireview evaluates and summarizes the progress in the synthesis of highly fluorinated aryl‐S^VI compounds at all levels, discussing synthetic strategies, reactivity, the advantages and disadvantages of the synthetic procedures, the proposed mechanisms, and the potential upcoming opportunities.

Chemoselective Hydro(Chloro)pentafluorosulfanylation of Diazo Compounds with Pentafluorosulfanyl Chloride

Pentafluorosulfanyl chloride (SF₅ Cl) is the most prevalent reagent for the incorporation of SF₅ group into organic compounds. However, the preparation of SF₅ Cl often relies on hazardous reagents and specialized apparatus. Herein, we described a safe and practical synthesis of a bench-stable and easy-to-handle solution of SF₅ Cl in n-hexane under gas-reagent-free conditions. The synthetic application of SF₅ Cl was demonstrated through the unprecedented reaction with diazo compounds. The chemoselective hydro- and chloropentafluorosulfanylations of α-diazo carbonyl compounds were developed in the presence of K₃ PO₄ or copper catalyst, respectively. These reactions provide a direct and efficient access to various α-pentafluorosulfanyl carbonyl compounds of high value for potential applications.