Benzylamine → 4-Benzylimino-6,7-dimethoxy-2-methyl-3,4-dihydro-2H-quinoline-1-carboxylic acid benzyl ester

HRID 370032Notes

Reaction equation

HRID 370032 reaction equation
C(OC([N:11]1[C:20]2[C:15](=[CH:16][C:17]([O:23][CH3:24])=[C:18]([O:21][CH3:22])[CH:19]=2)[C:14](=O)[CH2:13][CH:12]1[CH3:26])=O)C1C=CC=CC=1.C([N:29]([CH2:32][CH3:33])CC)C.[CH2:34](N)[C:35]1[CH:40]=[CH:39][CH:38]=[CH:37][CH:36]=1.[C:42](=[O:45])([O-])[O-:43].[K+].[K+]>[Ti](Cl)(Cl)(Cl)Cl.O.ClCCl>[CH2:34]([O:43][C:42]([N:11]1[C:20]2[C:15](=[CH:16][C:17]([O:23][CH3:24])=[C:18]([O:21][CH3:22])[CH:19]=2)[C:14](=[N:29][CH2:32][C:33]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:26]=2)[CH2:13][CH:12]1[CH3:26])=[O:45])[C:35]1[CH:40]=[CH:39][CH:38]=[CH:37][CH:36]=1

Participants

8

Reactant 4

HCID 7504BenzylamineHCID 8471TriethylamineHCID 11430Potassium CarbonateHCID 15480673Benzyl 6,7-dimethoxy-2-methyl-4-oxo-1,2,3,4-tetrahydroquinoline-1-carboxylate

Product 1

HCID 154806744-Benzylimino-6,7-dimethoxy-2-methyl-3,4-dihydro-2H-quinoline-1-carboxylic acid benzyl esterYield 219.1%

Reagents, catalysts & solvents 3

HCID 24193Titanium TetrachlorideCatalystHCID 962WaterSolventHCID 6344DichloromethaneSolvent2×

Procedure

6,7-Dimethoxy-2-methyl-4-oxo-3,4-dihydro-2H-quinoline-1-carboxylic acid benzyl ester (0.83 g, 2.3 mmol) was dissolved in a solution of triethylamine (2.2 mL, 2.3 mmol), benzylamine (0.55 mL, 5.1 mmol), and anhydrous dichloromethane (15 mL). This solution was stirred in a room temperature water bath as 2.5 mL of 1M solution of titanium tetrachloride (TiCl4) in dichloromethane (2.5 mmol) was slowly added. The reaction was allowed to stir at room temperature for 48 h. The reaction mixture was then poured into a stirred solution of water (50 mL) and potassium carbonate (10 g). After filtration, the filtrate was extracted with ethyl acetate (3×100 mL), the combined organic phases washed with water (100 mL), brine (50 mL), dried over sodium sulfate, filtered, and concentrated in vacuo to give the desired imine (1.12 g, ca. 100%). 1H NMR (CDCl3) δ 1.2 (d, 3H), 2.7-2.9 (m, 2H), 3.7 (s, 3H), 3.9 (s, 3H), 4.6 (d, 1H), 4.7 (d, 1H), 5.0-5.2 (m, 2H), 5.4 (d, 1H), 7.2-7.5 (m, 11H), 7.8 (s, 1H).

Workup

  1. additionwas slowly added
  2. filtrationAfter filtration
  3. extractionthe filtrate was extracted with ethyl acetate (3×100 mL)
  4. washthe combined organic phases washed with water (100 mL), brine (50 mL)
  5. dry with materialdried over sodium sulfate
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-001abd7707e8464aad8a22ca34492b08
Source dataset
uspto-grants-2000_10
Patent number
US06140342

Reaction notes

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