Grupo de Química Organometálica, Departamento de Química Inorgánica, Universidad de Murcia, Apartado 4021, 30071, Murcia, Spain.
Org Biomol Chem. 2011 Apr 7;9(7):2279-85. doi: 10.1039/c0ob00982b. Epub 2011 Feb 10.
A straightforward synthesis of substituted 1,2-dihydroquinazolinium triflates (3) is reported by reaction of 2-imino-substituted anilines with a range of carbonyl compounds in the presence of triflic acid via intermediate iminium salts. Similar reactions with di- or trialdehydes and triflic acid give bis- or tris-(1,2-dihydroquinazolinium) salts. Some 4-methyl substituted 1,2-dihydroquinazolinium salts rearrange, under various conditions, to their corresponding 4-iminium-1,2,3,4-tetrahydroquinolinium isomers (7). Most of salts 3 derived from ketones are rather unstable, which prevents their isolation or full characterization. The crystal structures of various 3 and 7 salts have been determined.
报道了一种通过 2-亚氨基取代苯胺与一系列羰基化合物在三氟磺酸存在下经亚胺盐中间体反应来合成取代的 1,2-二氢喹唑啉鎓三氟甲磺酸酯（3）的简便方法。类似的与二醛或三醛和三氟磺酸的反应得到双-或三-（1,2-二氢喹唑啉鎓）盐。一些 4-甲基取代的 1,2-二氢喹唑啉鎓盐在各种条件下重排为其相应的 4-亚氨基-1,2,3,4-四氢喹啉鎓异构体（7）。大多数由酮衍生的盐 3 非常不稳定，这阻止了它们的分离或完全表征。已确定了各种 3 和 7 盐的晶体结构。
