K2CO3-Catalyzed Rapid Conversion of N-Sulfonylhydrazones to Sulfinates

Thionyl fluoride as a sulfur(IV) SuFEx hub for the efficient syntheses of sulfinamides and sulfinate esters

Herein, we demonstrate a method for the syntheses of sulfinamides and sulfinate esters using a novel sulfur(IV) fluoride exchange reaction with organometallic reagents. Our strategy involves the addition of an amine or alcohol nucleophile to thionyl fluoride, acting as a S(IV) SuFEx hub, followed by an organometallic reagent. This approach allows efficient access to sulfinamides (45-91% yields) and sulfinate esters (44-82% yields) in only 30 minutes. The sulfinamide and sulfinate esters also can be readily derivatized to the corresponding S(VI) sulfonamides, sulfonate esters, sulfonimidamides, and sulfonimidates without isolation of the intermediates.

Synthesis of Multifluoromethylated γ-Sultines by a Photoinduced Radical Addition-Polar Cyclization

Despite the significance of sultines in synthesis, medicine, and materials science, the chemistry of sultines has remained unexplored due to their inaccessibility. Herein, we demonstrate the development of a photoredox-catalyzed multifluoromethyl radical addition/SO₂ incorporation/polar cyclization cascade approach to multifluoromethylated γ-sultines. The reactions proceed by single electron transfer induced multifluoromethyl radical addition to an alkene followed by SO₂ incorporation, and single-electron reduction for polar 5-exo-tet cyclization. Key to the success of the protocol is the use of easily oxidizable multifluoroalkanesulfinates as bifunctional reagents. The reactions proceed with excellent functional-group tolerance to deliver γ-sultines in moderate to excellent yields.

Pd-Catalyzed Rearrangement Reaction of N-Tosylhydrazones Bearing Allyl Ethers Into Trans-Olefin-Substituted Sulfonylhydrazones

A novel and efficient rearrangement of N-tosylhydrazones bearing allyl ethers into trans-olefin-substituted sulfonylhydrazones is proposed. The reaction involves breakage of the C-O bond and formation of the C-N bond. The reaction can be extended to a wide range of substrates, and the target products can be synthesized smoothly, regardless of the presence of electron-donating and electron-withdrawing groups. The proposed strategy is a new direction in the field of rearrangement reactions.