In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 3543-73-5 as follows. 3543-73-5
[0079] To a solution of 81.3 g (650.6 mmol) 2-bromoethanol, 1 g potassium iodide and 100 g water was added 17.0g (65 mmol) compound (6). The reaction mixture was heated to 65-70 C and held at this temperature for 8 h to 12 h.The pH value of the solution was held between 4.2-5.5 during this period by dropwise addition of a solution of 20.0 g(151.4 mmol) diammonium hydrogen phosphate in 35 g water. The control of pH over the duration of the reaction waseffected through use of a pH electrode. The conversion was followed by HPLC. The reaction was continued until thefraction of compound (7A) was ? 1.5 %. Thereby ca. 8% of compound (7B) had formed and the proportion of compound(7) was ca. 87%. The reaction mixture was subsequently concentrated to dryness at ca. 55-60 C under vacuum. Tothe residue was added 150 g water and, preferably with an alkali metal carbonate, the pH value adjusted to ca. 8.5. Thedesired product (7) was extracted with 200 g methylene chloride or 225 g chloroform, and the organic phase subsequentlywashed with 60 – 80 g water. The organic phase was then concentrated to dryness and the remaining oil or alreadycrystalline residue dissolved in 200 g ethyl acetate or alternatively in 60 g actetonitrile. Compound (7) crystallised at ca.5 C and was filtered under suction, washed with 20 g cold ethyl acetate or alternatively with 15 g cold acetonitrile anddried at 60 -70 C. The yield of compound (7) was 18.3 g (52.4 mmol) with a content of ? 98.2% (80.5 % of theory). Thecrude product contained ?0.6% compound (7A) and compound (7B) respectively as well as 99.2%, wherein compound (7A)was removed below a content of 0.2 % and compound (7B) below 0.3 %. Through the course of the reaction, the contentof compound (7C) was kept below 0.15 %, as this compound can only poorly be removed by recrystallization from theabove described solvents. The overall yield of this step was 76.5% of theory and was thus ca. 12.5% higher than thatdescribed in the procedure using ethylene oxide as according to DD34727 and ca. 31% higher in comparison to thefavoured procedure of W02011079193 involving addition of Huenig?s base.Example 5: Synthesis of ethyl 4-[5-[bis(2-hydroxyethyl)amino]-1-methyl-1H-benzimidazol-
According to the analysis of related databases, 3543-73-5, the application of this compound in the production field has become more and more popular.
Reference:
Patent; HEYL Chemisch-Pharmazeutische Fabrik GmbH und Co. KG; Frey, Michael; Walther, Dirk-Detlef; EP2690096; (2014); A1;,
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem