The thioamidation of gem-dibromoalkenes in an aqueous medium

Abstract

Direct installation of amine and sulphur with 1, 1-dibromoalkenes for thioamide synthesis has been achieved in a water medium. Presented green protocol bears more selectivity for thioamide with synthetic utility....

Water Mediated Direct Thioamidation of Aldehydes at Room Temperature

“…Similar results were observed for the reaction of 1a with dimethylamine 2a in water as well. However, when dimethylamine 2a in water was mixed with elemental sulfur, a detectable color change was observed indicating the formation of polysulfide 8 . , Subsequent addition of aldehyde 1a in THF gave the expected product 3aa . The formation of thioamide under these conditions implies that polysulfide 8 bears nucleophilic sulfur, which reacts with aldehyde 1a to give the expected product.…”

“…The search for innovative protocols with alternative synthetic strategies remains fascinating. As a direct consequence, recently we reported thioamidation reaction of gem -dibromoalkenes in a water medium . We found that dissolved amine in water will bring elemental sulfur into an aqueous phase followed by thioamidation of the gem -dibromoalkenes at elevated temperatures .…”

“…8 We found that dissolved amine in water will bring elemental sulfur into an aqueous phase followed by thioamidation of the gemdibromoalkenes at elevated temperatures. 8 With sustained interest in the development of novel synthetic strategies, we intended to develop an innovative protocol for the synthesis of thioamides. Structurally diverse thioamides are the precursor for the synthesis of many heterocyclic and natural products.…”

“…As a direct consequence, recently we reported thioamidation reaction of gem -dibromoalkenes in a water medium . We found that dissolved amine in water will bring elemental sulfur into an aqueous phase followed by thioamidation of the gem -dibromoalkenes at elevated temperatures . With sustained interest in the development of novel synthetic strategies, we intended to develop an innovative protocol for the synthesis of thioamides.…”

“…We envisioned that thioamidation of reactive aldehyde could be possible with initially prepared polysulfide , by dissolving amine in water and elemental sulfur. Reaction requirements may not rely on the high temperature by taking the advantage of the hydrophobic effect of water.…”