Ethyl 2,4-dimethyl-6-oxo-1-phenyl-1,6-dihydropyridine-3-carboxylate → 2,4-Dimethyl-6-oxo-1-phenyl-1,6-dihydropyridine-3-carboxylic acid

HRID 222796Notes

Reaction equation

HRID 222796 reaction equation
C([O:3][C:4]([C:6]1[C:11]([CH3:12])=[CH:10][C:9](=[O:13])[N:8]([C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)[C:7]=1[CH3:20])=[O:5])C>CO.[OH-].[Na+]>[CH3:20][C:7]1[N:8]([C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)[C:9](=[O:13])[CH:10]=[C:11]([CH3:12])[C:6]=1[C:4]([OH:5])=[O:3]

Participants

4

Reactant 1

HCID 11651942Ethyl 2,4-dimethyl-6-oxo-1-phenyl-1,6-dihydropyridine-3-carboxylate

Product 1

HCID 398703892,4-Dimethyl-6-oxo-1-phenyl-1,6-dihydropyridine-3-carboxylic acidYield 54%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 14798Sodium HydroxideSolvent

Procedure

A mixture of 2,4-dimethyl-6-oxo-1-phenyl-1,6-dihydro-pyridine-3-carboxylic acid ethyl ester (108 mg, 0.398 mmol) in methanol (0.8 mL) and 32% aq. NaOH (0.25 mL) was shaken at 60° for 22 hrs (after 5 hours only 70% conversion was observed). The reaction mixture was quenched with water (5 ml), extracted with ether (3×2 ml), and acidified 3M HCl (1 mL, pH=0). The title compound was separated by filtration to give 52.1 mg of colorless solid, yield 54%. LC-MS (m/z) 244.5 (MH+); tR=0.54. 1H NMR (600 MHz, DMSO-d6): 1.94 (s, 3H, 2-Me), 2.19 (d, J=0.9 Hz, 3H, 4-Me), 6.29 (s, 1H, 5-H), 7.25 (dm, J=7.7 Hz, J<1.5 Hz, 2H, two ortho-H of Ph), 7.47 (tt, J=7.4 Hz, J=1.2 Hz, 1H, para-H of Ph), 7.53 (tm, J=7.5 Hz, J<1.7 Hz, 2H, two meta-H of Ph), 13.26 (br. s, 1H, CO2H).

Workup

  1. customThe reaction mixture was quenched with water (5 ml)
  2. extractionextracted with ether (3×2 ml)
  3. customThe title compound was separated by filtration

Sources & evidence

ORD record
ord-1141a8129420453eab8d337207632766
Source dataset
uspto-grants-2012_06
Patent number
US08207347B2

Reaction notes

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