Ionic Liquid as Soluble Support for Synthesis of 1,2,3-Thiadiazoles and 1,2,3-Selenadiazoles

Abstract

A convenient synthesis of 1,2,3-thiadiazoles and 1,2,3-selenadiazoles was achieved using an ionic liquid as a novel soluble support. Ionic liquid-supported sulfonyl hydrazine was synthesized and reacted with a number of ketones to afford the corresponding ionic liquid-supported hydrazones that were converted to 1,2,3-thiadiazoles in the presence of thionyl chloride. The reaction of ionic liquid-supported hydrazones with selenium dioxide in acetonitrile afforded 1,2,3-selenadiazoles. The advantages of this methodology were the ease of workup, simple reaction conditions, and high purity.

Synthesis of 4‐Aryl‐1,2,3‐Thiadiazoles via NH4I‐Catalyzed Cyclization of N‐Tosylhydrazones with Sulfur

“…At the same time, it is widely used as a useful organic intermediate in synthetic chemical reactions . In general, the synthesis of 1,2,3‐thiadiazole mainly includes the following aspects: (a) diazotized α‐aminoketones react with Lawesson reagents; (b) the Hurd−Mori reaction; (c) the reaction of diazomethane with phenyl isothiocyanate; (d) 1,3‐dipolar cycloaddition of diazoalkanes to thiocarbonyl compounds; [3+2] cycloaddition of α‐enolic dithioesters with tosyl azide; and (f) the reaction of lithium (trimethylsilyl)diazomethane with thiocarbonyl compounds . However, these methods developed often suffer from limitations including potentially explosive materials(the diazo compounds and azide), require air‐sensitive reagents(SOCl 2 , and SCl 2 ), harsh reaction conditions, and narrow substrate scope.…”

Synthesis of Organochalcogen Compounds using Non-Conventional Reaction Media

“… Synthesis of IL‐supported sulfonyl hydrazones 139 followed by synthesis of 1,2,3‐thiadiazoles 138 and selenadiazoles 140 …”

Heterocycles-Based Ionic Liquid-Supported Synthesis of Small Organic Molecules

“…Anil Kumar and coworkers have also reported the synthesis of IL-grafted sulfonyl hydrazine 87 and reacted with various ketones to afford the resultant IL-supported hydrazones (Scheme 10) [41]. IL-bound hydrazones were converted to 1,2,3-selenadiazoles 88 and 1,2,3-thiadiazoles 89 in the presence of selenium dioxide and thionyl chloride, respectively.…”