4-Quinolinecarboxylic acid → 1,2,3,4-Tetrahydroquinoline-4-carboxylic acid

HRID 553011Notes

Reaction equation

HRID 553011 reaction equation
[N:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[C:4]([C:11]([OH:13])=[O:12])=[CH:3][CH:2]=1>[OH-].[K+]>[NH:1]1[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH:4]([C:11]([OH:13])=[O:12])[CH2:3][CH2:2]1

Participants

3

Reactant 1

HCID 102434-Quinolinecarboxylic acid

Product 1

HCID 139310671,2,3,4-Tetrahydroquinoline-4-carboxylic acid

Reagents, catalysts & solvents 1

HCID 14797Potassium HydroxideSolvent

Procedure

Quinoline-4-carboxylic acid (580 mg, 3.35 mmol) was dissolved in an aqueous potassium hydroxide solution (1 M, 10 mL). Nickel/aluminum amalgam (3 g) was added in portions over 1.5 hours. The heterogeneous mixture was stirred at room temperature for 48 hours. Upon completion, the reaction was filtered through Celite® and washed with ethyl acetate. The pH of the aqueous layer was adjusted with concentrated hydrochloric acid to 4-5. Solid sodium chloride was added until the aqueous layer was saturated. The ethyl acetate layer was separated. The aqueous phase was extracted with ethyl acetate. The extracts were combined, washed with minimal brine, dried over sodium sulfate, filtered, and concentrated. 1,2,3,4-Tetrahydro-quinoline-4-carboxylic acid was used without further purification (389 mg, 66%). 1H-NMR (CDCl3) δ: 1.95-2.08 (m, 1H), 2.22-2.37 (m, 1H), 3.23-3.34 (m, 1H), 3.39-3.49 (m, 1H), 3.79 (dd, 1H), 6.56 (d, 1H), 6.69 (dd, 1H), 7.07 (dd, 1H), 7.17 (d, 1H). MS m/z: 178 (M+1).

Workup

  1. filtrationUpon completion, the reaction was filtered through Celite®
  2. washwashed with ethyl acetate
  3. additionSolid sodium chloride was added until the aqueous layer
  4. customThe ethyl acetate layer was separated
  5. extractionThe aqueous phase was extracted with ethyl acetate
  6. washwashed with minimal brine
  7. dry with materialdried over sodium sulfate
  8. filtrationfiltered
  9. concentrationconcentrated
  10. custom1,2,3,4-Tetrahydro-quinoline-4-carboxylic acid was used without further purification (389 mg, 66%)

Sources & evidence

ORD record
ord-28466621f30f48139f044a0a5951ca45
Source dataset
uspto-grants-2011_05
Patent number
US07951950B2

Reaction notes

Loading…