Manganese-Catalyzed Electrochemical Diazidation of Dehydroalanine Peptides.

Dehydroalanine (Dha), a readily introducible non-canonical amino acid, is widely used for protein post-translational modification (PTM) and site-specific labeling of peptides and proteins. Despite its growing applications in biological systems, the precise modification of unnatural amino acid peptides and their conversion into functionalized endogenous peptides remain underdeveloped. To address this challenge, a novel peptide modification strategy is developed based on a manganese-catalyzed electrochemical radical relay process between dehydroalanine peptides and sodium azide.

Nickel-Catalyzed Electroreductive Heck Reaction: A Divergent Synthesis of C7- or C2-Arylindolines.

Herein, we present a novel electrochemically driven nickel-catalyzed Heck reaction of readily available -arylacrylindoles for the construction of both 7-arylindolines and 2-arylindolines. The reaction proceeds in an undivided electrochemical cell and employs a sacrificial zinc anode as the reductant. This catalytic protocol features a consecutive electroreductive process under exceedingly mild reaction conditions, with moderate yields.

Direct Electrooxidative Selenylation/Cyclization of Alkynes: Access to Functionalized Benzo[]furans.

A mild, practical, metal and oxidant-free methodology for the synthesis of various C-3 selenylated benzo[]furan derivatives was developed through the intramolecular cyclization of alkynes promoted with diselenides via electrooxidation. A wide range of selenium-substituted benzo[]furan derivatives were obtained in good to excellent yields with high regioselectivity under constant current in an undivided cell equipped with carbon and platinum plates as the anode and cathode, respectively. Moreover, the convergent approach exhibited good functional group tolerance and could be easily scaled up with good efficiency, providing rapid access to a diverse range of selenylated benzo[]furans derivatives from simple, readily available starting materials.

Electrochemical regioselective C-H selenylation of 2-indazole derivatives.

Selenium-substituted heteroarenes are biologically active compounds and useful building blocks. In this study, we have developed a metal- and oxidant-free, environmentally friendly protocol for the regioselective selenylation of 2-indazole derivatives by an electrochemical strategy. A number of selenylated 2-indazoles with a wide range of functional groups have been synthesized in moderate to good yields under mild and environment-friendly reaction conditions.

Direct Electrochemical Selenylation/Cyclization of Alkenes: Access to Functionalized Benzheterocycles.

A catalyst-free, environmentally friendly, and efficient electrochemical selenylation/cyclization of alkenes has been developed with moderate to excellent yields. This selenylated transformation proceeds smoothly and tolerates a wide range of synthetically useful groups to deliver diverse functionalized benzheterocycles, including iminoisobenzofuran, lactones, oxindoles, and quinolinones. Moreover, the present synthetic route could also be readily scaled up to gram quantity with convenient operation in an undivided cell.