3-ethyl-2-propylquinoline derivatives have been synthesized in a "one-pot" reaction from aromatic amine and w-butylaldehyde using p-methylbenzenesulfonic acid (TsOH) as promoting agent. The effect of the ratio of substrates, solvent and substituents of aniline were systematiclly investigated. Furthermore, the comparison of different Bronsted acids on the yield and selectivity were also studied, and the structure of products were characterized by NMR. The results show that when TsOH was used as promoting agent, aniline reacted with n-butylaldehyde affording 3-ethyl-2-propylquinoline in good yield of 59% with 40% by-product (N-butylaniline). Molybdophosphoric acid, concentrated sulfuric acid, could selectively afforded quinoline derivatives, too, but the yield was very low, only 28%, 24% respectively. Moreover, the effect of substituents of aniline on the yield of quinolines was also investigated. The electron-donating substituents were propitious to form quinoline derivatives, whereas the electron-withdrawing substituents were not in favor of quinoline derivatives. And the mechanism of formation of quinoline derivatives was proposed.%以芳胺和正丁醛为原料,对甲基苯磺酸(TsOH)为促进剂,采用“一锅法”合成了3-乙基-2-丙基喹啉衍生物,系统地考察了原料比例、溶剂以及芳胺上取代基对反应的影响,比较了不同的质子酸促进剂对喹啉衍生物产率以及选择性的影响,并对产物进行了核磁共振表征.实验结果表明当用对甲基苯磺酸( TsOH)为促进剂时,3-乙基-2-丙基喹啉收率可达到59％,同时生成40％ N-丁基苯胺；磷钼酸、浓硫酸也可以选择性地得到喹啉衍生物,但收率较低,分别只有28％和24％.同时,考察了苯胺环上取代基对喹啉收率的影响,当苯环上有供电子基时,有利于喹啉的生成,而吸电子基则不利于喹啉的生成.并推测了反应机理.
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