| 摘要 |
A process for the preparation of N,N-dimethyl-N'-(2-bromo-4-methyl-phenyl)-triazene of the formula <IMAGE> comprising (a) reacting N-acetyl-p-toluidine of the formula <IMAGE> with bromine at a temperature between about 0 DEG and 100 DEG C., to give the intermediate product of the formula <IMAGE> (b) reacting the intermediate product with hydrochloric acid by either (i) adding a dilute solution of aqueous hydrochloric acid to the intermediate product in its reaction solution and heating the mixture to a temperature between about 50 DEG and 120 DEG C., or (ii) precipitating the intermediate product from its reaction solution by mixing with water and filtering off, and without purification or drying heating the precipitate with dilute aqueous hydrochloric acid to a temperature between about 50 DEG and 120 DEG C., thereby to form a solution of 2-bromo-4-methylaniline hydrochloride, (c) reacting the resulting aqueous solution with an alkali metal nitrite at a temperature between about -20 DEG and +30 DEG C., and (d) reacting the product with dimethylamine at a temperature between about 0 DEG and 50 DEG C. |
