Methylhydrazine → HCID 67315103, compound

HRID 1011900Notes

Reaction equation

HRID 1011900 reaction equation
[CH2:1]([O:3][C:4](=[O:18])[C:5](=O)[CH:6]([CH3:16])[C:7]([C:9]1[CH:14]=[CH:13][CH:12]=[C:11]([Br:15])[CH:10]=1)=O)[CH3:2].BrC1C=C(C(=O)CC)C=CC=1.C(OCC)(=O)C(OCC)=O.[CH3:40][NH:41][NH2:42]>CO>[CH2:1]([O:3][C:4]([C:5]1[N:41]([CH3:40])[N:42]=[C:7]([C:9]2[CH:14]=[CH:13][CH:12]=[C:11]([Br:15])[CH:10]=2)[C:6]=1[CH3:16])=[O:18])[CH3:2].[CH2:1]([O:3][C:4]([C:5]1[C:6]([CH3:16])=[C:7]([C:9]2[CH:14]=[CH:13][CH:12]=[C:11]([Br:15])[CH:10]=2)[N:41]([CH3:40])[N:42]=1)=[O:18])[CH3:2]

Participants

7

Reactant 4

HCID 6061MethylhydrazineHCID 7268Diethyl OxalateHCID 882721-Propanone, 1-(3-bromophenyl)-HCID 673147814-(3-Bromo-phenyl)-3-methyl-2,4-dioxo-butyric acid ethyl ester

Product 2

HCID 67315103HCID 67315103, compoundHCID 673152765-(3-bromo-phenyl)-1,4-dimethyl-1H-pyrazole-3-carboxylic acid ethyl ester

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Conditions

Temperature
65 °C

Procedure

4.00 g (8.02 mmol) of 4-(3-bromo-phenyl)-3-methyl-2,4-dioxo-butyric acid ethyl ester (synthesized from 3′-bromopropiophenone and diethyl oxalate, following a procedure described in Ksander, Gary M.; McMurry, John E.; Johnson, Mark. A method for the synthesis of unsaturated carbonyl compounds. Journal of Organic Chemistry (1977), 42(7), 1180-5) were dissolved in 12.20 ml of MeOH and 0.37 g (8.02 mmol) of methylhydrazine were added. The reaction was heated under reflux (65° C.) for 1 h. Then the reaction was partitioned between chilled aqueous 1N HCl/EtOAc (3×). The organic phase was washed with aqueous 1N HCl, with aqueous sat. NaCl, dried (Na2SO4) and evaporated. The crude product was purified by flash chromatography (SiO2, n-heptane/EtOAc 99:1) to give 0.61 g of 5-(3-bromo-phenyl)-2,4-dimethyl-2H-pyrazole-3-carboxylic acid ethyl ester as yellow oil (MS: 323.2 MH+, Br) and 1.731 g of 5-(3-bromo-phenyl)-1,4-dimethyl-1H-pyrazole-3-carboxylic acid ethyl ester as yellow oil (MS: 323.2 MH+, Br).

Workup

  1. temperatureThe reaction was heated
  2. customThen the reaction was partitioned
  3. temperaturebetween chilled aqueous 1N HCl/EtOAc (3×)
  4. washThe organic phase was washed with aqueous 1N HCl, with aqueous sat. NaCl
  5. dry with materialdried (Na2SO4)
  6. customevaporated
  7. customThe crude product was purified by flash chromatography (SiO2, n-heptane/EtOAc 99:1)

Sources & evidence

ORD record
ord-5b4c4370bd6743a9a8d4199f98df0b4e
Source dataset
uspto-grants-2011_07
Patent number
US07977358B2

Reaction notes

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