Iodine‐Mediated Three‐Component Strategy to Synthesize 2‐Aminothiazoles from β‐Diketones/β‐ketoesters, Arylamines and Ammonium Thiocyanate

Abstract

A one‐pot, three‐component protocol for the synthesis of 2‐aminothiazoles promoted by iodine from readily available starting materials such as β‐diketones/β‐ketoesters, arylamines, and NH4SCN has been developed. A wide range of arylamines was tolerated well to produce the expected polysubstituted 2‐aminothiazoles in moderate to good yields. The characteristic features of this methodology include operational ease, metal‐free reaction conditions, gram‐scale scalability, functional group tolerance, and short reaction times.

Iodine and DMSO as Surrogate of Hazardous Metal and Non‐Metal Reagents in Organic Synthesis

“…Philips and the group have been able to achieve the task of preparation of 2-aminothiazoles using simple precursors like 1, 3 dicarbonyls, aniline derivatives and ammonium thiocynate (Scheme 25 (h)). [261] They used 1.0 equivalent of iodine and DMSO as the solvent system for the completion of reaction at 90 °C with considerable yield percentage up to 82 %. The use of any other iodine sources and replacement of solvent by any other solvents are found less effective in terms of the yield of desired products.…”

“…Despite all of these quite diverse and effective methods, most of them are muddled by substrate scope, unavailable precursors and use of unpredictable reagents. Philips and the group have been able to achieve the task of preparation of 2‐aminothiazoles using simple precursors like 1, 3 dicarbonyls, aniline derivatives and ammonium thiocynate (Scheme 25 (h)) [261] . They used 1.0 equivalent of iodine and DMSO as the solvent system for the completion of reaction at 90 °C with considerable yield percentage up to 82 %.…”