Oxolinic acid → 3-Quinolinecarboxylic acid, 1,4-dihydro-6,7-dihydroxy-1-ethyl-4-oxo-
Reaction equation
[CH2:1]([N:3]1[C:12]2[C:7](=[CH:8][C:9]3[O:15]C[O:13][C:10]=3[CH:11]=2)[C:6](=[O:16])[C:5]([C:17]([OH:19])=[O:18])=[CH:4]1)[CH3:2].B(Br)(Br)Br.[OH-].[K+]>O>[OH:15][C:9]1[CH:8]=[C:7]2[C:12](=[CH:11][C:10]=1[OH:13])[N:3]([CH2:1][CH3:2])[CH:4]=[C:5]([C:17]([OH:19])=[O:18])[C:6]2=[O:16]Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
1.4-Dihydro-1-ethyl-6,7-methylenedioxy-4-oxoquinoline-3-carboxylic acid (3.9 g) and boron tribromide (15 ml) were heated at 50° C. for 15 hours. The reaction mixture was cooled and added slowly to water (100 ml) at 0° C. The pH was adjusted to 11 with concentrated potassium hydroxide, the mixture was filtered and the filtrate taken to pH1, whereupon the precipitate was collected by filtration, washed with water and dried to give 1,4-dihydro-6,7-dihydroxy-1-ethyl-4-oxoquinoline-3-carboxylic acid (3.13 g); δ ((CD3)2SO) 1.42(3H,t); 4.46(2H,q); 7.23(1H,s); 7.66(1H,s); 8.82(1H,s)ppm.
Workup
- temperatureThe reaction mixture was cooled
- filtrationthe mixture was filtered
- filtrationwas collected by filtration
- washwashed with water
- customdried
Sources & evidence
- ORD record
- ord-0872327a78f3481b8092275f8f211e95
- Source dataset
- uspto-grants-1993_08
- Patent number
- US05232918
Reaction notes
Loading…