Triethylamine → 6-Fluoro-1-(4-fluorophenyl)-1,4-dihydro-4-oxo-7-(5-benzyl-2,5-diazabicyclo(2.2.1)hept-2-yl)quinoline-3-carboxylic acid

Participants

Reaction Steps

To a solution of 1.5 g (4 m Mol) of the mixed anhydride of 6,7-difluoro-1-(4-fluorophenyl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid with difluoroboronic acid in 10 ml of dimethylsulfoxide was added 0.9 g (4.78 m Mol) 2-benzyl-2.5-diazabicyclo(2.2.1)heptane and 0.4 g (4 m Mol) of triethylamine. After stirring for 4 hrs at room temperature, 150 ml of ether was added and the crystals that formed were collected by filtration. The residue was heated in a mixture of 60 ml dioxane and 90 ml 1.5N NaOH and heated at 100° C. for 1 hr. The hot solution was filtered to removed non-dissolved material. The solution was neutralized with conc HCl and the resultant crystals collected, washed with water and left to dry in the air. After recrystallization from DMF, 1.23 g (63%) of the product was obtained, mp 275° -280° dec.

Provenance & Evidence