| 摘要 |
In a process for the diazotization of amines there are simultaneously and continuously introduced into a precooled solvent or diluent, in which the reaction mixture accumulates in the course of the reaction, a diazotisable amine in the free state or in the form of a salt, if desired in admixture with a suitable solvent and a diazotizing agent, i.e. an agent yielding nitrous acid under the reaction conditions and also one or more acids and, if desired, one or more diluents and/or catalysts known to be suitable for the desired diazotization reaction, the rate of addition of the individual reactants being regulated according to the desired composition of the reaction product and the latter being continuously withdrawn. The process may be carried out using a single stirring vessel, optionally followed by an additional reaction chamber into which the mixture flowing off may be led to avoid contamination with fresh reactants and to complete the reaction, or the reaction mixture may be pumped in a cycle, preferably with turbulent flow. An apparatus is described with reference to the Figure (not shown) for carrying out the process. Starting materials mentioned include mono- and polyamines of aromatic character derived e.g. from benzene or hydrocarbons with condensed benzene nuclei or with one or more attached heterocyclic rings, e.g. quinoline or heterocyclic compounds such as thiophene, pyridine and pyrazole, optionally with aliphatic or araliphatic side chains and other substituents such as phenolic, carboxylic and sulphonic acid and halogen substituents. Diazotizing agents specified include inorganic nitrites with mineral acid, alkyl nitrites and nitrosyl-sulphuric acid. Examples relate to the diazotization of aniline (1); 1-phenyl-2 : 3-dimethyl - 4 - aminopyrazolone - (5) (2); sulphanilic acid (3); p-nitraniline (4); 2:4-dinitraniline (5); and para-amino-para1-methoxy diphenylamine hydrochloride. |
