Lithium Hydroxide → 2-carboxy-4-benzyloxyquinoline

HRID 6683Notes

Reaction equation

HRID 6683 reaction equation
C([O:8][C:9]([C:11]1[CH:20]=[C:19]([O:21][CH2:22][C:23]2[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=2)[C:18]2[C:13](=[CH:14][CH:15]=[CH:16][CH:17]=2)[N:12]=1)=[O:10])C1C=CC=CC=1.[Li+].[OH-]>C1COCC1>[C:9]([C:11]1[CH:20]=[C:19]([O:21][CH2:22][C:23]2[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=2)[C:18]2[C:13](=[CH:14][CH:15]=[CH:16][CH:17]=2)[N:12]=1)([OH:10])=[O:8]

Participants

4

Reactant 2

HCID 3939Lithium HydroxideHCID 220174862-Benzyloxycarbonyl-4-benzyloxyquinoline

Product 1

HCID 117808812-carboxy-4-benzyloxyquinolineYield 105.8%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

2-carboxy-4-hydroxyquinoline (5 g, 1.0 eq) was dissolved in 50 mL DMF. Cesium carbonate (20 g, 2.3 eq) was added to the solution and the resulting reaction mixture was heated at 50° C. for 20 minutes. Benzyl bromide (10 g, 2.1 eq) was added. The resulting reaction mixture was stirred at 50° C. for 1 hour. Then the reaction mixture was poured into 500 mLice-water, the precipitate was collected by filtration, and dried in vacuo to afford 2-benzyloxycarbonyl-4-benzyloxyquinoline (9.1 g). 2-benzyloxycarbonyl-4-benzyloxyquinoline (9.0 g) was dissolved in 50 mL THF, and 2 N LiOH solution (20 mL) was added, and the resulting reaction mixture was stirred at ambient temperature for 2 hours. The solvent was then removed in vacuo, and the residue acidified by the addition of 2N NaHSO4 to pH 3–4. The white precipitate was collected to afford 2-carboxy-4-benzyloxyquinoline (7.2 g), which was used without further purification.

Workup

  1. customthe resulting reaction mixture
  2. customThe solvent was then removed in vacuo
  3. additionthe residue acidified by the addition of 2N NaHSO4 to pH 3–4
  4. customThe white precipitate was collected

Sources & evidence

ORD record
ord-ef9c288f8f7f4b24b03af86766954c93
Source dataset
uspto-grants-2006_08
Patent number
US07084142B2

Reaction notes

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