p-Toluenesulfonic acid → 9-Methyl-2-propyl-4H-pyrido[1,2-a]pyrimidin-4-one

HRID 1580941Notes

Reaction equation

HRID 1580941 reaction equation
[NH2:1][C:2]1[C:7]([CH3:8])=[CH:6][CH:5]=[CH:4][N:3]=1.[C:9]([CH2:14][C:15](OC)=[O:16])(=O)[CH2:10][CH2:11][CH3:12].C1(C)C=CC(S(O)(=O)=O)=CC=1>COCCO>[CH3:8][C:7]1[C:2]2=[N:1][C:9]([CH2:10][CH2:11][CH3:12])=[CH:14][C:15](=[O:16])[N:3]2[CH:4]=[CH:5][CH:6]=1

Participants

5

Reactant 3

HCID 6101p-Toluenesulfonic acidHCID 153472-Amino-3-methylpyridineHCID 121700Methyl 3-oxohexanoate

Product 1

HCID 123397189-Methyl-2-propyl-4H-pyrido[1,2-a]pyrimidin-4-one

Reagents, catalysts & solvents 1

HCID 80192-MethoxyethanolSolvent

Conditions

Temperature
-30 °C

Procedure

A solution of 54.0g of 2-amino-3-methylpyridine, 144.0g of methyl butyrylacetate, 5.0g of p-toluenesulfonic acid, and 750ml of ethylene glycol monomethyl ether is heated in a nitrogen atmosphere, under reflux, for 60 hours. The solution is concentrated to dryness in vacuo, and the residual oil extracted with two 250ml portions of pentane. The pentane solution is concentrated to a volume of 250ml and cooled at -30°C to yield the title compound, melting point 59°-60°C.

Workup

  1. temperatureunder reflux, for 60 hours
  2. concentrationThe solution is concentrated to dryness in vacuo
  3. extractionthe residual oil extracted with two 250ml portions of pentane
  4. concentrationThe pentane solution is concentrated to a volume of 250ml

Sources & evidence

ORD record
ord-2ee1cbf26f2e46e4a3dca42e0247362c
Source dataset
uspto-grants-1976_01
Patent number
US03935197

Reaction notes

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