An Extrusion Strategy for On-Demand SF5Cl Gas Generation from a Commercial Disulfide

Synthesis of Pentafluorosulfanylated Ynamides and Further Functionalizations

Herein is described the first synthesis of SF5-ynamides, versatile building blocks featuring the pentafluorosulfanyl motif. This synthesis proceeds through a two-step sequence of radical SF5-addition onto the π-system of a wide range of terminal ynamides and derivatives substituted with various nitrogen fragments followed by a dehydrochlorination reaction. A selection of downstream functionalization reactions, including nucleophilic additions, cycloadditions, and sulfur ylide synthesis, highlights the wide-ranging applications of this novel type of functionalized SF5-building block.

Photo-induced hydroxypentafluorosulfanylation of alkenes with SF5Cl and oxygen gas and their further derivatization

Fluorinated or fluoroalkylated alcohols are common structural motifs in biologically active molecules, natural products, and pharmaceuticals. However, pentafluorosulfanyl (SF5) alcohols, a unique class of SF5 compounds that serve as synthetically valuable building blocks, are difficult to prepare with current methodologies. In this article, we present a single-step, metal-free, and photo-induced hydroxypentafluorosulfanylation of styrenes or α,β-unsaturated esters/amide, producing a series of structurally diverse pentafluorosulfanyl alcohols with up to 89% yields. This reaction is mild and operationally simple, using molecular oxygen as the hydroxy source. The protocol is suitable for a wide range of alkenes, including natural products and drug molecule derivatives. The formed SF5 alcohol units can be readily converted into diverse functionalized SF5 compounds, such as α-SF5 ketones, SF5 diols, and SF5 cyclic carbonates. The potential applications of these SF5 compounds in pharmaceutical and material sciences are vast, making this research a step forward in the field.

Expanding Radical Chloropentafluorosulfanylation of Alkynes

The chloropentafluorosulfanylation of alkynes is a delicate but crucial operation for accessing SF5-alkynes that serve as substrates in numerous transformations. Dolbier's procedure using Et3B/O2 was the most efficient approach, while recent efforts make use of other initiators and light activation. We found that THF, as a single stimulus, is sufficient to trigger the reaction of SF5Cl with alkynes. We determined the configuration of Cl/SF5 products and clarified the structure of side-products.