Mediator-free electrochemical trifluoromethylation: a cascade approach for the synthesis of trifluoromethylated isoxazolines.

The developed methodology describes an environmentally benign protocol for electro-oxidative CF3-radical generation, followed by cascade cyclization fabricating an isoxazoline scaffold from a ß,γ-unsaturated oxime. Consecutive C-O and C-C bond formations were achieved through this method featuring mild, robust, and scalable reaction conditions and broad substrate scope. Mechanistic studies revealed the necessity of anodic oxidation for the cascade process. Further conversion of the isoxazoline afforded other valuable derivatives.

Membrane transport inspired hydrolysis of non-activated esters at near physiological pH.

A positively charged micelle loaded with substrates was transported selectively to the reaction site (cathode) to promote the proximity and localization of the reactants (ester and hydroxide). The guided vehicular delivery coupled with electrolysis allows the hydrolysis of non-activated esters at near physiological pH with significant yields along with recyclability.

Highly Diastereoselective Synthesis of Dihydro-benzoimidazo-[1,3]-thiazines via Electro-oxidative Selenocyclization of Thioallyl Benzoimidazoles.

The current methodology reveals a green and proficient electro-oxidative tandem selenocyclization of thioallyl benzoimidazoles manufacturing selenylated dihydro-benzoimidazo-thiazine derivatives. Both C-Se and C-N bond formation were achieved via this mild protocol which exhibits good functional group tolerability affording an extensive range of substrate scope up to 96% isolated yields. Complete control over the regioselective formation of the six-membered heterocycle and stereoselective construction of the contiguous stereocenters was established. The practical electrochemical method operates in an undivided cell at ambient temperature without using any metal and external chemical oxidant.

Manganese-Catalyzed Electrochemical Tandem Azidation-Coarctate Reaction: Easy Access to 2-Azo-benzonitriles.

A one-pot cascade transformation consisting of an electrochemically driven azidation of 2H-indazole followed by coarctate fragmentation is developed to synthesize the 2-azo-benzonitrile motif. This manganese-catalyzed transformation is external-chemical-oxidant-free and operates at ambient temperature under air. This methodology exhibits good functional group tolerance, affording a broad range of substrate scopes of up to 89% isolated yield. Diverse derivatization of the 2-azo-benzonitrile product resulted in other valuable scaffolds.

Manganese-catalyzed Electro-oxidative Azidation-annulation Cascade to Access Oxindoles and Quinolinones.

An environmentally benign and proficient electro-oxidative tandem azidation-radical cyclization strategy is reported. Manganese-catalyzed electrochemical reaction in an undivided cell at room temperature and the use of NaN3 as the cheapest azide source are the key features of this protocol. Using this approach, a series of oxindole and quinolinone derivatives are synthesized in high yields. The synthesized azide functionality was efficiently converted to various valuable derivatives.

Regioselective C-H Sulfonylation of 2H-Indazoles by Electrosynthesis.

This study reveals a transition-metal- and external oxidant-free electrochemical method for the C3-H sulfonylation of biologically diverse 2H-indazoles at room temperature and under ambient air. Using various sulfonyl hydrazides as the sulfonyl precursor, a series of sulfonylated indazole derivatives containing a broad spectrum of functional groups were synthesized in up to 92% yield. Mechanistic studies suggest a precedented radical pathway is operating in the electrochemical process.