反应详情

Anhydrous piperazine (10.3 g) and 1-ethyl-6-fluoro-7-chloro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid ethyl ester were added to a mixture of pyridine (9 ml) and toluene (18 ml), and the mixture was refluxed with stirring for 5 hrs. The same procedure as described in Example 1 was followed to give 8.4 g (81% yield) of 1-ethyl-6-fluoro-7-(1-piperazinyl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid ethyl ester. mp: 178.5°-180° C.

1. temperaturethe mixture was refluxed