An Easy, General and Practical Method for the Construction of Alkyl Sulfonyl Fluorides
A visible light-induced reductive addition of 1°, 2° and 3° alkyl iodides to ethenesulfonyl fluoride, employing Hantzsch ester as a hydrogen source at room temperature was developed. This method featured a wide substrate scope and great functional group compatibility, providing facile and robust process to alkyl sulfonyl fluorides including enzyme inhibitors, natural products and drugs derivatives in up to 99percent yield. Further derivatization of resultant aliphatic sulfonyl fluorides was also achieved through sulfur fluoride exchange (SuFEx) reactions to deliver sulfonates and sulfonamides as privileged motifs for medicinal chemistry. (Figure presented.).
Oxidation of disulfides with electrophilic halogenating reagents: Concise methods for preparation of thiosulfonates and sulfonyl halides
The reaction of aromatic or benzylic disulfides with 2.5 equiv of Selectfluor in acetonitrile/water (10:1) at room temperature efficiently produced the corresponding thiosulfonates. Conversely, the reaction of disulfides with 6.5 equiv of Selectfluor or thiosulfonates with 4.5 equiv of Selectfluor in refluxing acetonitrile/water (10:1) provided sulfonyl fluorides in high yields. Accufluor and FP-T300 are also effective in preparing sulfonyl fluorides from disulfides under the similar reaction conditions. Sulfonyl chlorides or sulfonyl bromides were effectively obtained from the reaction of disulfides with 6 equiv of either N-chlorosuccinimide or N-bromosuccinimide in acetonitrile/water (10:1) at room temperature. Some other electrophilic chlorinating or brominating reagents are also able to be used instead of N-chlorosuccinimide or N-bromosuccinimide for the syntheses of sulfonyl halides from disulfides. These reactions of disulfides with electrophilic halogenating reagents are convenient methods to prepare thiosulfonates and sulfonyl halides.
Oxidation of disulfides with Selectfluor: Concise syntheses of thiosulfonates and sulfonyl fluorides
The reaction of aromatic or benzylic disulfides with 2.5 equiv of Selectfluor in acetonitrile/water (10:1) at room temperature efficiently produced the corresponding thiosulfonates. On the other hand, the reaction of disulfides with 6.5 equiv of Selectfluor in refluxing acetonitrile/water (10:1) provided sulfonyl fluoride in high yields.