Acetic Acid → 2-bromo-1-[3-methyl-1-(propan-2-yl)-1H-1,2,4-triazol-5-yl]ethan-1-one

HRID 886101ノート

反応式

HRID 886101 の反応式
C([O:3][C:4]([C:6]1[N:7]([CH:12]([CH3:14])[CH3:13])[N:8]=[C:9]([CH3:11])[N:10]=1)=O)C.[Br:15][CH2:16]Br.C[Li].C(O)(=O)C>C1COCC1.O>[Br:15][CH2:16][C:4]([C:6]1[N:7]([CH:12]([CH3:14])[CH3:13])[N:8]=[C:9]([CH3:11])[N:10]=1)=[O:3]

参加物

7

反応物 4

HCID 176Acetic AcidHCID 3024DibromomethaneHCID 582047541H-1,2,4-Triazole-5-carboxylic acid, 3-methyl-1-(1-methylethyl)-, ethyl esterHCID 178418348HCID 178418348、化合物

生成物 1

HCID 582048242-bromo-1-[3-methyl-1-(propan-2-yl)-1H-1,2,4-triazol-5-yl]ethan-1-one

試薬・触媒・溶媒 2

HCID 962Water溶媒HCID 8028Tetrahydrofuran溶媒

反応条件

温度
-78 °C

実験手順

To a solution of 2-isopropyl-5-methyl-2H-[1,2,4]triazole-3-carboxylic acid ethyl ester (12.09 g, 61.3 mmol) and dibromomethane (8.63 mL, 122.6 mmol) in THF (500 mL) at −78° C. was added methyllithium (40.9 mL, 122.6 mmol, 3M solution in diethoxymethane) dropwise. The reaction mixture was stirred at −78° C. for 15 min. Acetic acid (3 mL) was added and the reaction mixture allowed to warm to RT. The reaction mixture was diluted with water and extracted with ethyl acetate (3×30 mL). The combined organic extracts were washed with brine, dried (MgSO4) and concentrated in vacuo. The resultant residue was subjected to flash chromatography (SiO2, gradient 0-100% ethyl acetate in cyclohexane) to give 2-Bromo-1-(2-isopropyl-5-methyl-2H-[1,2,4]triazol-3-yl)-ethanone as a colourless oil which crystallised on standing (11.26 g, 75%). 1H NMR 400 MHz (CDCl3) δ: 5.41 (1H, sept, J=6.6 Hz), 4.67 (2H, s), 2.44 (3H, s), 1.49 (6H, d, J=6.6 Hz)

後処理

  1. temperatureto warm to RT
  2. extractionextracted with ethyl acetate (3×30 mL)
  3. washThe combined organic extracts were washed with brine
  4. dry with materialdried (MgSO4)
  5. concentrationconcentrated in vacuo

出典と根拠

ORDレコード
ord-a207fc73dba7488ca7c0659fa0eb5797
出典データセット
uspto-grants-2012_08
特許番号
US08242104B2

反応ノート

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