4-Azido-2(1H)-quinolones 1 are thermolyzed in the presence of carboxylic acids and polyphosphoric acid to yield oxazolo[4,5-c]quinolones 3. Formation of other possible isomeric ring closure products such as oxazolo[5,4-c]quinolones 2 or isoxazolo[4,3-c]quinolones 4 could be excluded by independent syntheses.
在羧酸和多磷酸的存在下,将4-Azido-2(1 H)-喹诺酮1进行热解,生成oxazolo [4,5- c ] quinolones3 。形成其他可能的异构闭环产物,例如oxazolo [5,可以通过独立的合成方法排除4- c ]喹诺酮2或异恶唑并[4,3- c ]喹诺酮4。