Reaction #931703

Reaction equation

dihexylamine

1,2-dihydro-2-oxoquinoline-3-carboxylic acid

N-methylmorpholine

isobutyl chlorocarbonate

→

N,N-dihexyl-1,2-dihydro-2-oxoquinoline-3-carboxamide

Yield 75.8%

Solvents

tetrahydrofuran

N,N-dimethylformamide

Conditions

Workup

1. 1
   workup.STIRRINGAfter stirring at −15° C. for 4 hours
2. 2
   Concentrationat room temperature overnight, the reaction mixture was concentrated under reduced pressure
3. 3
   workup.ADDITIONthe residue, after addition of ethyl acetate
4. 4
   Washwas washed with water, 1N hydrochloric acid
5. 5
   Dryinga saturated aqueous sodium bicarbonate solution and a saturated aqueous sodium chloride solution, and dried over anhydrous sodium sulfate
6. 6
   OtherAfter removal of the drying agent
7. 7
   Filtrationby filtration
8. 8
   Concentrationthe filtrate was concentrated under reduced pressure
9. 9
   OtherThe residue was recrystallized from hexane

Procedure

In a mixture of 50 ml of tetrahydrofuran and 250 ml of N,N-dimethylformamide were dissolved 9.46 g of 1,2-dihydro-2-oxoquinoline-3-carboxylic acid and 5.06 g of N-methylmorpholine, and after cooling to −15° C., 6.83 g of isobutyl chlorocarbonate was added dropwise over 10 minutes. After stirring at −15° C. for 10 minutes, 9.73 g of dihexylamine was added dropwise over 5 minutes. After stirring at −15° C. for 4 hours and then at room temperature overnight, the reaction mixture was concentrated under reduced pressure, and the residue, after addition of ethyl acetate, was washed with water, 1N hydrochloric acid, a saturated aqueous sodium bicarbonate solution and a saturated aqueous sodium chloride solution, and dried over anhydrous sodium sulfate. After removal of the drying agent by filtration, the filtrate was concentrated under reduced pressure. The residue was recrystallized from hexane to give 13.51 g of N,N-dihexyl-1,2-dihydro-2-oxoquinoline-3-carboxamide.

Source