Synthesis of 8,9-difluoro-2-methyl-6-oxo-1,2-dihydropyrrolo[3,2,1-<b>ij</b>]quinoline-5-carboxylic acid
作者:Vinod D. Parikh、Andrew H. Fray、Edward F. Kleinman
DOI:10.1002/jhet.5570250558
日期:1988.9
A new and efficient seven-step synthesis of 8,9-difluoro-2-methyl-6-oxo-1,2-dihydropyrrolo[3,2,1-ij]-quinoline-5-carboxylic acid (9), an important intermediate used in the synthesis of quinolone antibacterials, has been developed beginning with commercially available 2,3,4-trifluoronitrobenzene. Selective displacement of the 2-fluorine of the starting material with the anion of ethyl acetoacetate and
一种重要的新方法,即高效的七步合成8,9-二氟-2-甲基-6-氧代-1,2-二氢吡咯并[3,2,1- ij ]-喹啉-5-羧酸(9)从商业上可获得的2,3,4-三氟硝基苯开始,已开发出用于合成喹诺酮类抗菌剂的中间体。用乙酰乙酸乙酯的阴离子选择性置换2-氟起始原料,然后水解和脱羧,得到芳基丙酮衍生物11。还原11的酮和硝基,然后与乙氧基亚甲基丙二酸二乙酯缩合,得到14,将其环化为吲哚衍生物15通过Mitsunobu程序。15的Friedel-Crafts环化反应和酸水解得到标题化合物9。