Introduction of a new synthetic route about 6-Aminobenzimidazole

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 6-Aminobenzimidazole, and friends who are interested can also refer to it.

934-22-5, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 934-22-5 name is 6-Aminobenzimidazole, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

General procedure: A mixture of compound II-1, II-2 or II-3 (2 mmol),SnCl2¡¤2H2O (10 mmol) in EtOAc (15 mL) was refluxed for12 h. When the reaction was complete according to TLCanalysis, the resulting reaction mixture was cooled to room temperature. Subsequently, the reaction mixture wasadjusted to pH 8-9 with saturated aq. NaHCO3 (50 mL).Then the mixture was extracted with EtOAc (2 ¡Á 150 mL).The combined organic phase was washed with brine (200mL), dried over anhydrous Na2SO4, and concentrated toafford compounds III-1, III-2 or III-3, which were useddirectly for the next step without further purification. To amixture of 5-amino-1H-benzimidazole (III-1, III-2 or III-3,2 mmol), water (5 mL) and concentrated HCl (12 mol/L,0.51 mL) at 0C, a solution of sodium nitrite (NaNO2, 2.1mmol) in water (10 mL) was added dropwise whilemaintaining the temperature below 5C. After stirring for 20min, a solution of diazonium chloride was prepared.Subsequently, a solution of diazonium chloride was addedgradually to a mixture of phenols (IV-1-IV-10, 2 mmol),sodium hydroxide (NaOH, 2 mmol), ethanol (15 mL) andwater (25 mL) at 0-5C. After the addition of the abovediazonium solution, the mixture was continued to stir for 3-6h until a lot of precipitate was produced. The solid wascollected, washed with water (3¡Á10 mL), dried and purifiedby PTLC to give the target products V-1~V-28.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 6-Aminobenzimidazole, and friends who are interested can also refer to it.

Reference:
Article; Ke, Yazhen; Zhi, Xiaoyan; Yu, Xiang; Ding, Guodong; Yang, Chun; Xu, Hui; Combinatorial Chemistry and High Throughput Screening; vol. 17; 1; (2014); p. 89 – 95;,
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem