Photoredox-catalyzed stereo- and regioselective vicinal fluorosulfonyl-borylation of unsaturated hydrocarbons.

There has been considerable research on sulfur(vi) fluoride exchange (SuFEx) chemistry, which is considered to be a next-generation click reaction, and relies on the unique balance between reactivity and stability inherent in high valent organosulfur. The synthetic versatility of the bifunctional handles containing the fluorosulfonyl group presents great synthetic value and opportunity for drug discovery. However, the direct photoredox-catalyzed fluorosulfonyl-borylation process remains unexplored and challenging due to its system incompatibility and limited synthetic strategies. Herein, we developed a sequential photocatalytic radical difunctionalization strategy for the highly efficient stereoselective synthesis of vicinal fluorosulfonyl borides (VFSBs) with an integrated redox-active SO2F radical reagent. The VFSBs acted as orthogonal synthons, and were subjected to a range of convenient transformations via the cleavage of the C-B and S(vi)-F bonds, including halogenation, Suzuki coupling, hydrogenation, and the SuFEX click reaction, which demonstrated the great potential of the VFSB moieties for use in skeleton linkage and drug modification.

Electrochemical Nickel-Catalyzed 1,2-Diarylation of 1,3-Dienes.

Due to the presence of carbon-carbon double bonds, 1,3-dienes exhibit great reactivity. A protocol for the site-selective diarylation of terminal 1,3-dienes is reported here. The transformation is facilitated by the Ni catalyst without the need for additional ligands, utilizing an electrochemical setup. Preliminary results indicate that by introducing chiral ligands moderate enantioselective diarylation products can be obtained. This method affords diversely substituted diarylated products that occur as structural motifs in various natural products.

Electrochemical-Promoted Nickel-Catalyzed Reductive Allylation of Aryl Halides.

Compared with conventional reductive coupling, reductive coupling under electrochemical conditions without external reductants is greener, milder, and more efficient and is of increasing interest to organic chemists. In this work, we report the sacrificial anode, nickel-catalyzed electrochemical allylation reaction of aryl and alkyl halides. The reaction can be applied to a range of allylation reagents such as trifluoroalkenes, oxalates, and acetates.