Methanol → 4-Oxo-4,5-dihydrothieno[3,2-c]quinoline-7-carboxylic acid

HRID 2420950Notes

Reaction equation

HRID 2420950 reaction equation
[O:1]=[C:2]1[C:11]2[CH:12]=[CH:13][S:14][C:10]=2[C:9]2[CH:8]=[CH:7][C:6]([C:15]([O:17]C)=[O:16])=[CH:5][C:4]=2[NH:3]1.CO.C1COCC1.[Li+].[OH-]>O>[O:1]=[C:2]1[C:11]2[CH:12]=[CH:13][S:14][C:10]=2[C:9]2[CH:8]=[CH:7][C:6]([C:15]([OH:17])=[O:16])=[CH:5][C:4]=2[NH:3]1

Participants

6

Reactant 4

HCID 887MethanolHCID 3939Lithium Hydroxide3×HCID 8028TetrahydrofuranHCID 50941659HCID 50941659, compound

Product 1

HCID 509417534-Oxo-4,5-dihydrothieno[3,2-c]quinoline-7-carboxylic acidYield 96.3%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Procedure

Methyl 4-oxo-4,5-dihydrothieno[3,2-c]quinoline-7-carboxylate (1.0 eq, 618 mg, 2.38 mmol) was suspended in 10 ml of a mixture of MeOH, THF, and water (1:1:1, v:v:v). LiOH (2.0 eq, 114 mg, 4.76 mmol) was added and the mixture was stirred at room temperature for 2 hours. An additional amount of LiOH (114 mg) was added and the mixture was stirred for an hour. LiOH (50 mg) was added and the mixture stirred for an additional 2 hours. Water was added and the solution filtered through a pad of celite. The pad of celite was thoroughly washed with aqueous 1 N NaOH. The solution was acidified with 6 N aqueous HCl to induce precipitation of the expected material. Filtration and drying afforded 4-oxo-4,5-dihydrothieno[3,2-c]quinoline-7-carboxylic acid as a yellow solid (562 mg, 96% yield). LCMS (ES): 95% pure, m/z 246 [M+1]+; 1H NMR (DMSO-d6, 400 MHz) δ 7.61 (d, J=5.2, 1H), 7.73 (dd, J=1.6, J=8.0, 1H), 7.88 (d, J=5.6, 1H), 7.92 (d, J=8.4, 1H), 8.02 (d, J=1.6, 1H), 11.92 (s, 1H), 13.21 (br. s, 1H) ppm.

Workup

  1. stirringthe mixture was stirred for an hour
  2. stirringthe mixture stirred for an additional 2 hours
  3. filtrationthe solution filtered through a pad of celite
  4. washThe pad of celite was thoroughly washed with aqueous 1 N NaOH
  5. customprecipitation of the expected material
  6. filtrationFiltration
  7. customdrying

Sources & evidence

ORD record
ord-38ac79e847a74d4995780020a7ff2476
Source dataset
uspto-grants-2011_06
Patent number
US07956064B2

Reaction notes

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