Application
In the pharmaceutical field, alpha-(2,4-Dichlorophenyl)-1H-imidazole-1-ethanol is an important precursor for the synthesis of various imidazole antifungal drugs (such as econazole and miconazole), which are widely used to treat fungal infections. Furthermore, it is an intermediate in the production of agricultural fungicides (such as imidazoles), which are used in agriculture to control various plant diseases, such as powdery mildew and black rot, thereby increasing crop yields.
Synthesis
General procedure for the synthesis of alpha-(2,4-dichlorophenyl)-1H-imidazole-1-ethanol from 2'-(1H-imidazol-1-yl)-2,4-dichloroacetophenone: In a 1000 mL three-necked flask equipped with a stirrer, a thermometer, and a dropping funnel, add 102 g of 2'-(1H-imidazol-1-yl)-2,4-dichloroacetophenone (0.4 mol) and 300 mL of methanol. Potassium borohydride was added in batches and slowly heated to reflux. After completion of the reaction, stirring was continued for 1 h and the progress of the reaction was monitored by thin layer chromatography (TLC) (unfolding agent was ethyl acetate: methanol = 10:1, v/v). At the end of the reaction, methanol was recovered by distillation under reduced pressure. The concentrate was adjusted to pH 4-5 with 5% hydrochloric acid solution and subsequently diafiltrated. The filtrate was adjusted pH to 7-8 with 5% sodium bicarbonate solution, when a white solid precipitated. The solid was collected by filtration, washed with water, dried and recrystallized to give 93.1 g of 1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethanol in 90.5% yield with a melting point of 134-135 °C.
References
[1] Patent: CN102180835, 2016, B. Location in patent: Paragraph 0015; 0016
[2] Bioorganic and Medicinal Chemistry, 2018, vol. 26, # 8, p. 1665 - 1674
[3] Polyhedron, 2013, vol. 52, p. 106 - 114
[4] Organic and Biomolecular Chemistry, 2018, vol. 16, # 23, p. 4288 - 4294
[5] Medicinal Chemistry Research, 1999, vol. 9, # 3, p. 162 - 175
