An Environment‐friendly Synthesis of 2,3‐Disubstituted‐2‐iminothiazoline‐4‐ones

Abstract

A series of 2,3‐substituted‐2‐iminothiazoline‐4‐ones derivatives have been synthesized via an improved method including an auto‐catalyzed reaction. This method avoided using any extra catalyst except for the reaction material. This method has been successful in both the aromatic substituted 2‐iminothiazolines and the alkyl substituted 2‐iminothiazolines. The special product with a hydroxyl group on the 2‐iminogroup of 1,3‐thiazoline‐4‐ones has also been obtained unexpectedly. The possible mechanism has been proposed for the special process of dealkylation and hydroxylation. This method offered a special way to afford the 2‐hydroxyimino‐substituted thiazoline‐4‐one derivatives in an efficient and eco‐friendly way. The mechanism of the transformation under acid condition has also been proposed.

3-Ethyl-2-(ethylimino)-4-methyl-2,3-dihydro-1,3-thiazole-5-carboxylate Ethyl Ester

“…This method offers an alternative way to provide 2,3-diethyl-2,3-dihydro-1,3-thiazole (1a) instead of the traditional two-step method from disubstituted thioureas and β-keto ester derivatives (Scheme 2). As part of our recent studies on the new biological heterocyclic compounds [12,13], we now report a successful simple procedure to synthesize 1a from ethyl acetoacetate (2a), NBS, and N,N′-diethylthiourea (4a). While 1a shares a similar structure with the reported analogues [8], it was still reported for the first time by our research group in this paper.…”

A mild one-pot synthesis of 2-iminothiazolines from thioureas and 1-bromo-1-nitroalkenes

“…Functionalized 2-iminothiazoline has been an important building block in organic chemistry. 1 Its derivatives show significant pharmacological activities such as bactericidal and fungicidal activity. 2 In addition, they are found in drug applications for treatment of allergies, hypertension, inflammations, bacterial and HIV infections.…”