Chemistry of Heterocyclic Compounds ( IF 1.5 ) Pub Date : 2020-10-17 , DOI: 10.1007/s10593-020-02793-3 Olga А. Storozhenko , Xiaoyi Yue , Alexey А. Festa , Alexey А. Varlamov , Leonid G. Voskressensky
Novel 2-amino-4-(nitromethylidene)chromenes were obtained as a result of the reaction of 1-(2-imino-2H-chromen-3-yl)pyridinium perchlorates and nitromethane by the action of DBU at reflux in trifluoroethanol. The starting 2-iminochromenes are readily accessible from the corresponding salicylic aldehydes and quaternary cyanomethyl pyridinium salts. The reaction is tolerant to substituents of different nature (alkyl, alkoxy, halogen); a limitation is the presence of strong electron-withdrawing substituents in the benzene ring of chromene. During the reaction, the products precipitate and can be isolated by filtration.
中文翻译:
在碱性介质中由1-(2-亚氨基-2-H-铬-3-基团)吡啶-1-鎓高氯酸盐和硝基甲烷合成2-氨基色烯衍生物
新的2-氨基-4-(nitromethylidene)色烯1-(2-亚氨基2的反应的结果,获得ħ -苯并吡喃-3-基)的三氟乙醇吡啶鎓高氯酸盐和硝基甲烷通过DBU的作用在回流。起始的2-亚氨基色酮易于从相应的水杨醛和季氰基甲基吡啶鎓盐获得。该反应可耐受不同性质的取代基(烷基,烷氧基,卤素);局限性是在色烯的苯环中存在强的吸电子取代基。在反应过程中,产物沉淀并且可以通过过滤分离。