Nucleophilic substitution of a 4-dimethylamino group in quinoline proton sponges. Stabilization of 4-quinolones in hydroxy form. Synthesis of a proton sponge based on 8-hydroxyquinoline
作者:Olga V. Dyablo、Alexander F. Pozharskii
DOI:10.1007/s10593-019-02587-2
日期:2019.11
Demethylation of methoxy groups in 6(8)-methoxy-2,4,5-tris(dimethylamino)quinolines with 48% HBr leads to nucleophilic substitution of the 4-NMe2 group with the formation of quinolones existing in solution and the solid state in the hydroxy form stabilized by intramolecular hydrogen bonding. Unlike HBr, the use of BBr3 in the case of the 8-methoxy derivative leads to the formation of 8-hydroxy-2,4
6(8)-甲氧基-2,4,5-三(二甲基氨基)喹啉中48%HBr的甲氧基脱甲基导致4-NMe 2基团的亲核取代,形成溶液中和固态存在的喹诺酮通过分子内氢键稳定的羟基形式 与HBr不同,在8-甲氧基衍生物的情况下使用BBr3会导致形成8-羟基-2,4,5-三(二甲基氨基)喹啉,这是一种有望与质子酸和路易斯酸结合的配体。