Benzylhydrazine dihydrochloride → methyl 1-benzyl-3-methyl-1H-pyrazole-4-carboxylate
Reaction equation
CN(/[CH:4]=[C:5](/[C:10](=O)[CH3:11])\[C:6]([O:8][CH3:9])=[O:7])C.Cl.Cl.[CH2:15]([NH:22][NH2:23])[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1>C(O)C>[CH2:15]([N:22]1[CH:4]=[C:5]([C:6]([O:8][CH3:9])=[O:7])[C:10]([CH3:11])=[N:23]1)[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 80 °C
Procedure
To a solution of (Z)-methyl 2-((dimethylamino)methylene)-3-oxobutanoate (15.8 g, 92.5 mmol) in ethanol (50 mL) was added 1-benzylhydrazine dihydrochloride (18 g, 92.3 mmol). The resulting solution was stirred for 3.5 h at 80° C., then concentrated under reduced pressure. The residue was dissolved in 200 mL of ethyl acetate. The organic layer was washed with 1×40 mL of water and 2×40 mL of brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by silica gel chromatography with ethyl acetate/petroleum ether (1:4) as the eluent to furnish 12.4 g (58%) of the title compound as a yellow solid.
Workup
- concentrationconcentrated under reduced pressure
- dissolutionThe residue was dissolved in 200 mL of ethyl acetate
- washThe organic layer was washed with 1×40 mL of water and 2×40 mL of brine
- dry with materialdried over anhydrous sodium sulfate
- concentrationconcentrated under reduced pressure
- customThe residue was purified by silica gel chromatography with ethyl acetate/petroleum ether (1:4) as the eluent
Sources & evidence
- ORD record
- ord-39f0383af1bf42949ccac08abbc295c5
- Source dataset
- uspto-grants-2016_08
- Patent number
- US09428502B2
Reaction notes
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