HCID 67916524, compound → 2-methyl-1H-1,5-naphthyridin-4-one

HRID 893616Notes

Reaction equation

HRID 893616 reaction equation
C(O[C:4](=[O:15])/[CH:5]=[C:6](\[NH:8][C:9]1[CH:10]=[N:11][CH:12]=[CH:13][CH:14]=1)/[CH3:7])C>C1(OC2C=CC=CC=2)C=CC=CC=1>[CH3:7][C:6]1[NH:8][C:9]2[C:10]([C:4](=[O:15])[CH:5]=1)=[N:11][CH:12]=[CH:13][CH:14]=2

Participants

3

Reactant 1

HCID 67916524HCID 67916524, compound

Product 1

HCID 122991332-methyl-1H-1,5-naphthyridin-4-oneYield 36.2%

Reagents, catalysts & solvents 1

HCID 7583Diphenyl EtherSolvent

Procedure

Ethyl-(Z)-3-(3-pyridylamino)-2-butenoate (8.0 g) (obtained as described in J. Royal Netherlands Chem. Soc., 1976, 95, 220) was added to a refluxing eutectic mixture of 26.5% v/v diphenyl and 73.5% v/v diphenyl oxide (20 ml). The solution was heated under reflux for 1 hour and then cooled. The precipitated solid was collected, washed with hexane (20 ml) and ether (20 ml), and then purified by flash chromatography, eluting initially with methanol/dichloromethane (1:4 v/v). There was thus obtained 2-methyl-1,7-naphthyridin-4-(1H)-one (0.96 g), as an off-white powder, m.p. >250° C. (sublimes); NMR (d6 -DMSO): 2.4(s,3H), 6.2(s,1H), 8.1(d,1H), 8.45(d,1H), 9.0(s,1H). Further elution of the chromatography column with aqueous ammonia/methanol/dichloromethane (2:99:99 v/v) gave the required 2-methyl-1,5-naphthyridin-4(1H)-one (D1) (2.25 g), as an off-white powder, m.p. >280° C. (decomp.); NMR: 2.65(s,3H), 6.65(s,1H), 7.6(dd,1H), 8.4(dd,1H), 8.8(dd,1H).

Workup

  1. temperatureThe solution was heated
  2. temperatureunder reflux for 1 hour
  3. temperaturecooled
  4. customThe precipitated solid was collected
  5. washwashed with hexane (20 ml) and ether (20 ml)
  6. custompurified by flash chromatography
  7. washeluting initially with methanol/dichloromethane (1:4 v/v)
  8. washFurther elution of the chromatography column with aqueous ammonia/methanol/dichloromethane (2:99:99 v/v)

Sources & evidence

ORD record
ord-1f4cc400c2a14b328e432e0fca23486a
Source dataset
uspto-grants-1992_06
Patent number
US05126344

Reaction notes

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