Methylhydrazine → 3-(3,4-dimethoxyphenyl)-1-methyl-1H-pyrazol-5(4H)-one

HRID 531186Notes

Reaction equation

HRID 531186 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH:14]=[CH:15][C:16]=1[O:17][CH3:18])[C:6]([CH2:8][C:9](OCC)=[O:10])=O.[CH3:19][NH:20][NH2:21]>C(O)C>[CH3:1][O:2][C:3]1[CH:4]=[C:5]([C:6]2[CH2:8][C:9](=[O:10])[N:20]([CH3:19])[N:21]=2)[CH:14]=[CH:15][C:16]=1[O:17][CH3:18]

Participants

4

Reactant 2

HCID 6061MethylhydrazineHCID 2758465Ethyl 3,4-dimethoxybenzoylacetate

Product 1

HCID 896499703-(3,4-dimethoxyphenyl)-1-methyl-1H-pyrazol-5(4H)-oneYield 44%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

Using General Procedure A; ethyl 3,4-dimethoxybenzoylacetate (5.00 g, 19.8 mmol, 1.1 equ.) in ethanol (60 mL) was treated at 0° C. with methylhydrazine (0.95 mL, 19.8 mmol, 1.0 equiv.) to give 3-(3,4-dimethoxyphenyl)-1-methyl-1H-pyrazol-5(4H)-one (1.86 g, 7.94 mmol, 44%) after purification by chromatography on silica gel (hexanes:ethyl acetate; 4:1 to 1:1) as a light yellow powder. 1H-NMR (400 MHz) CDCl3: 7.35-7.35 (d, 1H), 7.06-7.04 (dd, 1H), 6.87-6.85 (d, 1H), 3.94 (s, 3H), 3.92 (s, 3H), 3.57 (s, 2H), 3.39 (s, 3H), 13C-NMR (100 MHz) CDCl3: 171.6, 154.1, 151.1, 149.4, 124.1, 119.6, 110.7, 107.3, 55.9, 55.9, 38.0, 31.3; LC/MS-MS: 235.1→219.0 m/z; GS1 and GS2 at 30, DP=66, CE=33, CXP=14, tR=3.26 min.

Sources & evidence

ORD record
ord-eeda87f1b16343a584e64697044416b1
Source dataset
uspto-grants-2016_05
Patent number
US09353121B2

Reaction notes

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