In this paper, a simple, environment-friendly and efficient one-pot way to synthesize 2-amino-4-thiazolinones at room temperature was reported. Ethyl 2-thiocyanatoacetate was formed by substitution reaction of ethyl chloroacetate with thiocyanate in [Bmim]SCN. After that, when HOAc was employed as a catalyst, 2-amino-4-thiazolinones were produced in high yields through the nucleophilic attack of amines to ethyl 2-thiocyanatoacetate following ring-closing reaction of intermediate product S-alkyl isothioureas. As a task-specific ionic liquid, [Bmim]SCN plays a role of a solvent as well as a reactant. And it can be recycled. The crystal structure of 2-(4-ethylpiperzin-1-yl)-4-thiazolinone (3i) was confirmed by X-ray diffraction study.

Key words: thiazolinones, synthesis, task-specific ionic liquid, crystal structure