Electrochemical synthesis of versatile ammonium oxides under metal catalyst-, exogenous-oxidant-, and exogenous-electrolyte-free conditions

Abstract

An electrochemical oxidative cross-coupling reaction between 2.5-substituted-pyrazolin-5-ones and ammonium thiocyanate has been developed.

An environmentally benign way to synthesize 2-thiocyano-1,3-dicarbonyl compounds with high antifungal activity: a key role of solvent

“…As the first step, we explored the electrolysis of 3-benzylpentane-2,4-dione (1a) using NH 4 SCN as the supporting electrolyte in acetonitrile and methanol by analogy with the known methods of electrochemical thiocyanation of unsaturated bonds 58,61,76,77,[85][86][87][88][89] (Table 1). At first glance, it seemed that the 1,3-diketone/SCN − system was sufficient for the electrochemical synthesis of thiocyanated 1,3-dicarbonyl compounds.…”

“…Thus, researchers are trying to develop superior alternative thiocyanation protocols based on visible light [52][53][54][55][56] and electricity. [57][58][59][60][61][62][63] The low cost of electric current and wide opportunities to control the mechanisms of electrochemical reactions make organic electrosynthesis a powerful and environmentally friendly way to conduct redox processes. [64][65][66][67][68][69][70] Recently, electrochemical approaches have been actively applied to C-H functionalization.…”

Electrochemical Synthesis of Polysubstituted Sulfonated Pyrazoles via Cascade Intermolecular Condensation, Radical–Radical Cross Coupling Sulfonylation, and Pyrazole Annulation

“…Recently, with sulfonyl hydrazides, sulfinic acids, and sodium sulfinates as the sulfonyl source, the construction of sulfonyl-containing carbo- and heterocycles via electrochemical oxidative sulfonylation has received much attention and studies, since it can take place under catalyst- and exogenous-oxidant-free conditions (Scheme b). In addition, electrochemical oxidative cross-coupling reactions have also been successfully employed for the construction of thiocyanato pyrazoles and organylselanyl pyrazoles (Scheme c). Moreover, very recently, He and co-workers developed an electrochemical multicomponent reaction for synthesis of 4-selanylpyrazoles via the electrochemical oxidative cross-coupling of pyrazole (generated in situ by the cyclocondensation of 1,3-diketone and hydrazine) with diselenide (Scheme d) .…”

PhICl2-Mediated Regioselective and Electrophilic Oxythio/Selenocyanation of o-(1-Alkynyl)benzoates: Access to Biologically Active S/SeCN-Containing Isocoumarins

“…Among them, organic thiocyanated compounds and their selenylated analogs have attracted continuous attention of organic and medicinal chemists. They can be used as versatile building blocks to achieve various useful synthetic transformations since their thiocyanato and selenocyanato moieties can be readily converted to other sulfur and selenium-containing functional groups ( Castanheiro et al, 2016 ; Zhang et al, 2018 ; Wu et al, 2021 ; Yuan et al, 2021 ). In the meanwhile, naturally occurring or pharmaceutically interesting organothio/selenocyanates have been reported to show a broad spectrum of bioactivities ( Chen et al, 2007 ).…”