Triethylamine → diethyl 3-(p-chlorophenyl)-4-methyl-2-oxo-2H-pyrano[2,3-b]pyridine-6,7-dicarboxylate

HRID 864929Notes

Reaction equation

HRID 864929 reaction equation
[C:1]([C:4]1[C:9](=O)[NH:8][C:7]([C:11]([O:13][CH2:14][CH3:15])=[O:12])=[C:6]([C:16]([O:18][CH2:19][CH3:20])=[O:17])[CH:5]=1)(=O)[CH3:2].[Cl:21][C:22]1[CH:27]=[CH:26][C:25]([CH2:28][C:29]([OH:31])=[O:30])=[CH:24][CH:23]=1.C(N(CC)CC)C.[OH-].[NH4+]>C(OC(=O)C)(=O)C>[Cl:21][C:22]1[CH:23]=[CH:24][C:25]([C:28]2[C:29](=[O:31])[O:30][C:9]3=[N:8][C:7]([C:11]([O:13][CH2:14][CH3:15])=[O:12])=[C:6]([C:16]([O:18][CH2:19][CH3:20])=[O:17])[CH:5]=[C:4]3[C:1]=2[CH3:2])=[CH:26][CH:27]=1

Participants

6

Reactant 4

HCID 8471TriethylamineHCID 14923Ammonium HydroxideHCID 15880(4-Chlorophenyl)acetic acidHCID 13752508Diethyl 5-acetyl-1,6-dihydro-6-oxo-2,3-pyridinedicarboxylate

Product 1

HCID 19958229diethyl 3-(p-chlorophenyl)-4-methyl-2-oxo-2H-pyrano[2,3-b]pyridine-6,7-dicarboxylateYield 99.4%

Reagents, catalysts & solvents 1

HCID 7918Acetic AnhydrideSolvent

Procedure

Diethyl 5-acetyl-1,6-dihydro-6-oxo-2,3-pyridinedicarboxylate, (6.0 g, 0.0213 mol), 4-chlorophenyl acetic acid (3.64 g, 0.0213 mol) and triethylamine (3.0 g, 1.5 eq) are refluxed in 50 mL of acetic anhydride for three and one-half hours and then stirred at room temperature overnight. The reaction mixture is poured into 100 mL of ice cold water and the pH is adjusted to 8 with an ammonium hydroxide solution. The crystalline solid is filtered, washed with water, dried and dissolved in 100 mL of methylene chloride. The solution is dried over anhydrous sodium sulfate and the solvent removed under reduced pressure to give the desired product (8.8 g, 99%), which is crystallized from ethyl acetate to give the pure product having a melting point 179°-181° C.

Workup

  1. filtrationThe crystalline solid is filtered
  2. washwashed with water
  3. customdried
  4. dissolutiondissolved in 100 mL of methylene chloride
  5. dry with materialThe solution is dried over anhydrous sodium sulfate
  6. customthe solvent removed under reduced pressure

Sources & evidence

ORD record
ord-4900dfe30050464098e8debd4bd94804
Source dataset
uspto-grants-1996_10
Patent number
US05565412

Reaction notes

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