反应详情

温度

115 °C

A suspension of 8-chloro-7-fluoro-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine-3-carboxylic acid (1.6 g) and (RS)-2-(4-fluorophenyl)piperazine (3.7 g) in pyridine (16 cc) is heated to a temperature in the region of 115° C. for 24 hours. The reaction mixture is concentrated under reduced pressure (20 kPa) at approximately 60° C. The residue is taken up with ethanol (40 cc) and concentrated again under reduced pressure under the above conditions. The solid obtained is taken up with water (10 cc), treated with 10% strength acetic acid (1.75 cc), drained and washed with water (2×10 cc) and ethanol (2×10 cc). After 2 recrystallizations in dimethylformamide (10 cc each time), (RS)-7-fluoro-8-[3-(4-fluorophenyl)-1-piperazinyl]-1-methyl-4-oxo-1,4-dihydrobenzo[b ][1,8]naphthyridine-3-carboxylic acid (1.1 g) is obtained in the form of a yellow solid, m.p. 270°-275° C.

1. concentrationThe reaction mixture is concentrated under reduced pressure (20 kPa) at approximately 60° C
2. concentrationconcentrated again under reduced pressure under the above conditions
3. customThe solid obtained
4. washwashed with water (2×10 cc) and ethanol (2×10 cc)
5. customAfter 2 recrystallizations in dimethylformamide (10 cc each time)