Hydrochloric Acid → 4,5-Diethyl 1-methyl-1H-pyrazole-4,5-dicarboxylate

HRID 908208

反応式

HRID 908208 の反応式
[CH3:1][NH:2]N.Cl.[CH2:5]([O:7][C:8](=[O:21])[C:9](=[CH:17][N:18](C)C)[C:10](=O)[C:11]([O:13][CH2:14][CH3:15])=[O:12])[CH3:6]>C(O)C>[CH2:14]([O:13][C:11]([C:10]1[N:2]([CH3:1])[N:18]=[CH:17][C:9]=1[C:8]([O:7][CH2:5][CH3:6])=[O:21])=[O:12])[CH3:15]

参加物

5

反応物 3

HCID 313Hydrochloric AcidHCID 6061MethylhydrazineHCID 72733183Diethyl 2-((dimethylamino)methylene)-3-oxosuccinate

生成物 1

HCID 670417284,5-Diethyl 1-methyl-1H-pyrazole-4,5-dicarboxylate収率 36%

試薬・触媒・溶媒 1

HCID 702Ethanol溶媒

反応条件

温度
60 °C

実験手順

Under an atmosphere of argon, methylhydrazine (1.15 g, 25 mmol) and HCl (36.5% in water, 2.5 ml) were added to a solution of 2-dimethylaminomethylene-3-oxo-succinic acid diethyl ester (6.07 g, 25 mmol, obtained by the method of Hanzlowsky et al., J. Heterocyclic Chem. 2003, 40(3), 487-498) in ethanol (200 ml). The mixture was heated to 60° C. until HPLC analysis indicated the disappearance of the starting material (2 h). The solvent was evaporated, and the residue was taken up in dichloromethane and washed (water). The organic layer was dried (Na2SO4), the solvent was evaporated and the title compound (2.06 mg, 36%) was isolated from the mixture by column chromatography (silica gel, heptane:ethyl acetate=100:0-60:40). (The regioisomeric 1-methyl-1H-pyrazole-3,4-dicarboxylic acid diethyl ester can also be isolated, and can be distinguished from the desired product by NOE-1H-NMR.) MS (m/e)=227.2 [M+H+].

後処理

  1. customobtained by the method of Hanzlowsky et al., J
  2. customthe disappearance of the starting material (2 h)
  3. customThe solvent was evaporated
  4. washwashed (water)
  5. dry with materialThe organic layer was dried (Na2SO4)
  6. customthe solvent was evaporated

出典と根拠

ORDレコード
ord-b6a4c3bb3861473c88daae12daaa4959
出典データセット
uspto-grants-2011_09
特許番号
US08017604B2

関連ノート

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