Methanol → methyl 3-nitro-1H-pyrazole-5-carboxylate
Reaction equation
[N+:1]([C:4]1[NH:8][N:7]=[C:6]([C:9]([OH:11])=[O:10])[CH:5]=1)([O-:3])=[O:2].S(Cl)(Cl)=O.[CH3:16]O>>[N+:1]([C:4]1[NH:8][N:7]=[C:6]([C:9]([O:11][CH3:16])=[O:10])[CH:5]=1)([O-:3])=[O:2]Participants
4
Conditions
- Temperature
- 30 °C
Procedure
Into a round-bottom flask, which was purged and maintained with an inert atmosphere of nitrogen, was placed a solution of 5-nitro-1H-pyrazole-3-carboxylic acid (5.00 g, 31.9 mmol, 1.00 equiv) in methanol (150 mL). To this was added thionyl chloride (5.60 g, 47.8 mmol, 1.50 equiv) dropwise at 0° C. The resulting solution was stirred for 18 h at 30° C. in an oil bath, then concentrated under reduced pressure. The residue was purified using silica gel column chromatography with ethyl acetate/petroleum ether (1:30-1:10) as eluent to furnish 5.00 g (78%) of the title compound as a brown solid.
Workup
- customInto a round-bottom flask, which was purged
- temperaturemaintained with an inert atmosphere of nitrogen
- concentrationconcentrated under reduced pressure
- customThe residue was purified
Sources & evidence
- ORD record
- ord-3fc3ddfa04e74174bfa2919aaee655d4
- Source dataset
- uspto-grants-2014_10
- Patent number
- US08871790B2
Reaction notes
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