Superacidic Cyclization of Activated Anthranilonitriles into 2-Unsubstituted-4-aminoquinolines
作者:Hubert Lavrard、Paolo Larini、Florence Popowycz
DOI:10.1021/acs.orglett.7b01798
日期:2017.8.18
4-Aminoquinolines were prepared in a three-step synthesis starting from substituted anthranilonitriles. The condensation on 1,1,1-trichloro-4-ethoxybut-3-enone proceeded efficiently either neat or in refluxing EtOH. Cyclization in superacidic trifluoromethanesulfonic acid provided unstable intermediate, which upon treatment with NaOEt in ethanol, afforded the expected esters. Theoretical investigations
从取代的蒽腈开始,以三步合成的方式制备了4-氨基喹啉。在纯净或回流的EtOH中,在1,1,1-三氯-4-乙氧基丁-3-烯酮上的缩合反应有效进行。在超酸性三氟甲磺酸中环化可提供不稳定的中间体,将其在乙醇中用NaOEt处理后,可得到预期的酯。理论研究指出,在环化过程中,单质子化的硝基为反应性物种。