380177-22-0

6953-65-7

74-88-4

380177-22-0

The general procedure for the synthesis of 5-chloro-1-methyl-1H-benzo[d]imidazole-2-methanol from (6-chloro-1H-benzimidazol-2-yl)methanol and iodomethane was as follows: the N-methyl-2-methanol-5-chloro-benzimidazole 49 was prepared with reference to the method of Harisha et al. [28] (6-chloro-1H-benzimidazol-2-yl)methanol 28 (1.50 g , 8.20 mmol) and sodium hydroxide (0.33 g, 8.2 mmol) were dissolved in anhydrous acetone (30 mL) and stirred for 30 min. Subsequently, iodomethane (1.41 g, 8.20 mmol) was added and the reaction mixture continued to be stirred for 24 hours. Upon completion of the reaction, the mixture was concentrated to one-fourth of the original volume and poured into ice-cold water. The precipitated solid was collected and washed with 50% hydrochloric acid to neutralize the excess potassium carbonate. Next, the solids were washed sequentially with cold water (100 mL) and aqueous ethanol. Finally, the product was purified by column chromatography (eluent ratio 9:1 chloroform/ethanol) to afford the target compound 38 as bright orange crystals in 9% yield.