Choline, hydroxide → Choline 7-fluoro-8-[4-(4-fluorophenyl)piperazin-1-yl]-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

7.6 cm3 of a 45% solution of choline hydroxide in methanol were added to a suspension of 7.6 g of 7-fluoro-8-[4-(4-fluorophenyl)piperazin-1-yl]-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine-3-carboxylic acid in 75 cm3 of methanol. The reaction mixture was stirred for approximately 2 hours at approximately 25° C. The solution was filtered in order to remove a slight insoluble material and was concentrated at approximately 50° C. on a rotary evaporator at approximately 20 kPa. The residual solid was recrystallized from 70 cm3 of 2-propanol and 30 cm3 of methanol. The crystals were filtered off with 10 cm3 of 2-propanol on each occasion and dried in an oven at 100° C. at 10 kPa. 7.4 g of choline 7-fluoro-8-[4-(4-fluorophenyl)piperazin-1-yl]-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine-3-carboxylate were obtained in the form of a yellow solid melting at about 285-90° C.

Provenance & Evidence