Isopropanol → Levofloxacin

Participants

Reaction Conditions

Reaction Steps

5 g (17.79 mmole) of (S)-(−)-9,10-difluoro-3-methyl-7-oxo-2,3-dihydro-7H-pyrido [1,2,3-de][1,4]benzoxazine-6-carboxylic acid was put in suspension in 6.8 mL (0.06 mole) of N-methyl piperazine. The reaction mixture was heated to reflux for 40 minutes until completion of the reaction. The mixture was then cooled to 80° C. IPA (10 mL) and n-heptane (10 mL) were added at this temperature. The solid was filtrated under vacuum and rinsed with n-heptane. The mother liquor also gave a precipitate after addition of n-heptane. Both precipitates were filtrated under vacuum and dried overnight to yield 4.9 g (76%) levofloxacin.

Provenance & Evidence