反应详情

温度

120 °C

Ethyl 5-amino-7-fluoro-1-[2-(S)-fluoro-1-(R)-cyclopropyl]-1,4-dihydro-8-methyl-4-oxoquinoline-3-carboxylate (735 mg, 2.28 mmol) was dissolved in a 1:1 mixed solution (8 ml) of acetic acid:water, and after adding concentrated sulfuric acid (90 μl) thereto, it was stirred for 4 hours in an oil bath of 120° C. After cooling the reaction solution with ice, water (20 ml) was poured therein, and the mixed reaction solution was stirred at room temperature for 2 hours. The precipitated crystals were filtered out, washed with excess water, a small amount of cold ethanol and excess diethyl ether in that order, and then dried under a reduced pressure at 80° C. for 17 hours. 552 mg (82%) of the title compound was thereby obtained in the form of yellow crystals.

1. additionwas poured
2. customthe mixed reaction solution
3. stirringwas stirred at room temperature for 2 hours
4. filtrationThe precipitated crystals were filtered out
5. washwashed with excess water
6. dry with materiala small amount of cold ethanol and excess diethyl ether in that order, and then dried under a reduced pressure at 80° C. for 17 hours