| 摘要 |
FIELD: organic chemistry, chemical technology. ^ SUBSTANCE: invention relates to a method for preparing 7-aminopyrido[1,2-a] [1,3]-benzimidazole of the formula (1) that can be used as an intermediate product in synthesis of fluorescent and biologically active substances. Method involves stage for preparing N-(2,4-dinitrophenyl)pyridinium chloride by interaction of 2,4-dinitrochlorobenzene with pyridine and reduction of N-(2,4-dinitrophenyl)pyridinium chloride. Interaction of 2,4-dinitrochlorobenzene with pyridine is carried out at temperature 20oC for 1 h in the mole ratio 2,4-dinitrochlorobenzene : pyridine = 1:7, and reduction of salt SnCl2 . 2 H2O alcoholic solution is carried out in 3% HCl in the mole ratio N-(2,4-dinitrophenyl)pyridinium chloride : SnCl2 . 2 H2O = 1:6 at temperature 20oC for 0.12 h. Invention provides reducing cost of synthesis, diminishing time and temperature in carrying out the process, enhancing purity and the yield of the end product. ^ EFFECT: improved preparing method. ^ 2 cl, 2 ex |
