[1,2,4]Triazolo[1,5-a]pyrazine-2-carboxylic acid, ethyl ester, 3-oxide → HCID 67485099, compound

HRID 1016419Notes

Reaction equation

HRID 1016419 reaction equation
[N:1]1[C:2]([C:11]([O:13][CH2:14][CH3:15])=[O:12])=[N+:3]([O-])[N:4]2[CH:9]=[CH:8][N:7]=[CH:6][C:5]=12>P(OCC)(OCC)OCC>[CH2:14]([O:13][C:11]([C:2]1[N:1]=[C:5]2[CH:6]=[N:7][CH:8]=[CH:9][N:4]2[N:3]=1)=[O:12])[CH3:15]

Participants

3

Reactant 1

HCID 12308357[1,2,4]Triazolo[1,5-a]pyrazine-2-carboxylic acid, ethyl ester, 3-oxide

Product 1

HCID 67485099HCID 67485099, compoundYield 22.8%

Reagents, catalysts & solvents 1

HCID 31215Triethyl phosphiteSolvent

Procedure

Ethyl 1,2,4-triazolo[1,5-a]pyrazine-2-carboxylate-3-oxide (prepared as described in J. Chem. Soc., Perkin Trans. 1, 1976, 2166) (2.0 g, 9.6 mmol) was stirred in triethyl phosphite (20 ml) at 100° C. for 1 h. The solvent was concentrated in vacuo, and the crude product was triturated with diethyl ether (50 ml). The precipitated solid was separated by filtration, and purified by flash chromatography on silica gel, eluting with 1:1 dichloromethane:ethyl acetate, yielding [1,2,4]triazolo[1,5-a]pyrazine-2-carboxylic acid ethyl ester as a pale orange solid (420 mg). Data for the title compound: 1H NMR (360 MHz, CDCl3) δ 1.51 (3H, t, J=7.1 Hz), 4.59 (2H, q, J=7.1 Hz), 8.34 (1H, d, J=4.5 Hz), 8.63 (1H, d, J=4.5 Hz), 9.43 (1H, s); MS (ES+) m/e 193 [MH]+.

Workup

  1. concentrationThe solvent was concentrated in vacuo
  2. customthe crude product was triturated with diethyl ether (50 ml)
  3. customThe precipitated solid was separated by filtration
  4. custompurified by flash chromatography on silica gel
  5. washeluting with 1:1 dichloromethane

Sources & evidence

ORD record
ord-1b5af580deac4fb89792f6665a17468b
Source dataset
uspto-grants-2002_11
Patent number
US06476030B1

Reaction notes

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