Toluene → 8-Butylamino-6-methylpyrido[2,3-b]pyrazine-7-carboxylic acid, ethyl ester

HRID 1287234Notes

Reaction equation

HRID 1287234 reaction equation
[NH2:1][C:2]1[C:3]([NH:15][CH2:16][CH2:17][CH2:18][CH3:19])=[C:4]([C:10]([O:12][CH2:13][CH3:14])=[O:11])[C:5]([CH3:9])=[N:6][C:7]=1[NH2:8].O.[CH:21]([CH:23]=O)=O.C1(C)C=CC=CC=1>O>[CH2:16]([NH:15][C:3]1[C:2]2[C:7](=[N:8][CH:21]=[CH:23][N:1]=2)[N:6]=[C:5]([CH3:9])[C:4]=1[C:10]([O:12][CH2:13][CH3:14])=[O:11])[CH2:17][CH2:18][CH3:19]

Participants

5

Reactant 3

HCID 1140TolueneHCID 123876125,6-Diamino-4-butylamino-2-methylnicotinic acid ethyl esterHCID 21880647Glyoxal hydrate

Product 1

HCID 867340398-Butylamino-6-methylpyrido[2,3-b]pyrazine-7-carboxylic acid, ethyl esterYield 70%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

13.3 g. of 5,6-Diamino-4-butylamino-2-methylpyridine-3-carboxylic acid, ethyl ester (0.05 Mol.) of Example 1 d and 4g. of glyoxal monohydrate, dissolved in 100 ml. of toluene, are refluxed, while the water formed is removed by means of a water separator. After about 3 hours, the reaction is complete and the solution is concentrated. The remaining oily residue is extracted twice with 50 ml. portions of gasoline and addition of activated charcoal. The gasoline extracts are cooled and the crystalline 8-butylamino-6-methylpyrido[2,3-b]pyrazine-7-carboxylic acid, ethyl ester is filtered off, yield 70%; m.p. 56°-58°.

Workup

  1. customformed
  2. customis removed by means of a water separator
  3. concentrationthe solution is concentrated
  4. extractionThe remaining oily residue is extracted twice with 50 ml
  5. additionportions of gasoline and addition of activated charcoal
  6. temperatureThe gasoline extracts are cooled
  7. filtrationthe crystalline 8-butylamino-6-methylpyrido[2,3-b]pyrazine-7-carboxylic acid, ethyl ester is filtered off

Sources & evidence

ORD record
ord-3f9fa54314d14130898646f102829b27
Source dataset
uspto-grants-1976_10
Patent number
US03984412

Reaction notes

Loading…