Synthesis
GENERAL METHOD: Thiourea (0.04 mol) and iodine (0.02 mol) were ground homogeneously in a mortar and subsequently mixed with 4-chloropropiophenone (0.02 mol). The reaction mixture was heated in a water bath at 70°C with intermittent stirring for 8 hours. Upon completion of the reaction, the solid product was ground to a fine powder and washed with ether to remove unreacted 4-chloropropiophenone. Next, it was washed with 5% aqueous sodium thiosulfate to remove residual iodine and finally with distilled water. The crude product was dissolved in hot water and hot filtered to remove insoluble impurities. Ammonia was slowly added to the filtrate until 2-amino-4-(4'-chlorophenyl)-5-methyl-1,3-thiazole precipitated completely. The precipitate was collected and recrystallized with ethanol to give purified crystals of the target compound [9].
References
[1] Asian Journal of Chemistry, 2017, vol. 29, # 12, p. 2794 - 2798
[2] Journal of the Indian Chemical Society, 1960, vol. 37, p. 427 - 428
[3] Bioorganic and Medicinal Chemistry Letters, 2001, vol. 11, # 3, p. 313 - 317