Electrochemical C–H Sulfonylation of Hydrazones

Abstract

We have developed an electrochemical method for the direct C−H sulfonylation of aldehyde hydrazones using sodium sufinates as the sulfonylating agent under supporting electrolyte-free conditions. This straightforward sulfonylation strategy afforded a library of (E)-sufonylated hydrazones with high tolerance of various functional groups. The radical pathway of this reaction has been revealed by the mechanistic studies.Letter pubs.acs.org/OrgLett

Transition Metal and Base‐Free Electro‐Oxidative Regioselective Trifluoromethylation of Imidazo[1,2‐a]pyridines

“…Gratifyingly, mono-methyl and dimethyl substitution at diverse positions of the pyridine ring provided the desirable products (1-4) in admirable yields. Presumably, all the mono and di-halogen substituted substrates reacted smoothly and exhibited supreme efficacy towards the expected product (5)(6)(7)(8)(9)(10)(11)(12)(13) formation in pleasant yields ranging 71% to 78%. Similarly, strong electron-withdrawing groups like À CF 3 , À CN, À NO 2 and À CO 2 Et on pyridine rings were compatible producing respective products (14-17) in moderate yields (Scheme 3).…”

“…This sustainable platform proffers alternatives to super-stoichiometric oxidants or reductants and diminishes toxic by-products. [10] In the last decade, various electrochemical approaches for the CF 3 -radical generation [11] have been developed either by anodic oxidation or cathodic reduction of CF 3 precursors, followed by functionalization in a suitable organic framework. Recently, our group reported an electrochemical method for the trifluoromethylation of β,γ-unsaturated oximes towards the corresponding trifluoromethylated isoxazolines.…”

Electrochemical and photochemical reaction of isatins: a decade update

“…2,3 The advancement of new approaches to prepare these medicinally important molecules with zero waste could be an important agenda among synthetic organic chemists. In this regard, electro- 4 and photochemical 5 techniques are recognized as one of the energy-efficient and environment-friendly approaches as they use electrons or photons as activators and do not produce any harmful waste. In recent years extensive research has been done on the electro- and photochemical functionalization of isatins; however, no review exists for the electrochemical functionalization of isatins.…”

Photochemical and Electrochemical Synthesis of Oxazoles and Isoxazoles: An Update

“…[13][14][15][16][17][18] Therefore, synthesis of these two crucial heterocyclic compounds using various green and sustainable methodologies has garnered significant enthusiasm within the community of synthetic organic chemists. [19] In this regard, photochemical [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] and electrochemical [38][39][40][41][42][43][44][45][46][47][48][49][50] techniques are considered as one of the most energy-efficient and environment-friendly approaches as they use photon or electron as activators and do not produce harmful waste. In recent years, extensive research has been done on photochemical and electrochemical synthesis of oxazoles.…”