Methyl iodide → 3-(2,5-difluorophenyl)-1,4-dimethyl-5-(trifluoromethyl)-1H-pyrazole

HRID 1378291ノート

反応式

HRID 1378291 の反応式
Br[C:2]1[C:3]([C:12]2[CH:17]=[C:16]([F:18])[CH:15]=[CH:14][C:13]=2[F:19])=[N:4][N:5]([CH3:11])[C:6]=1[C:7]([F:10])([F:9])[F:8].[CH2:20]([Li])CCC.CI>C1COCC1>[F:19][C:13]1[CH:14]=[CH:15][C:16]([F:18])=[CH:17][C:12]=1[C:3]1[C:2]([CH3:20])=[C:6]([C:7]([F:10])([F:9])[F:8])[N:5]([CH3:11])[N:4]=1

参加物

5

反応物 3

HCID 6328Methyl iodideHCID 110569594-bromo-3-(2,5-difluorophenyl)-1-methyl-5-(trifluoromethyl)-1H-pyrazoleHCID 178418339Butyllithium

生成物 1

HCID 110656733-(2,5-difluorophenyl)-1,4-dimethyl-5-(trifluoromethyl)-1H-pyrazole収率 72.4%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

実験手順

A solution of 10 g of 4-bromo-3-(2,5-difluorophenyl)-1-methyl-5-(trifluoromethyl)-1H-pyrazole in 250 mL anhydrous THF was cooled to -78° C. and stirred with an overhead stirrer. The cold solution was treated with 12 mL of 2.5M n-butyllithium in hexanes never allowing the temperature to exceed -70° C. After stirring for 5 minutes, 1.9 mL of methyl iodide was added quickly. The cooling bath was removed and the solution allowed to warm to room temperature. The solution was diluted with diethyl ether and the combined organic extracts were washed twice with brine, dried over anhydrous magnesium sulfate and concd in vacuo. Chromatographic purification (silica, 5% ethyl acetate in hexanes) gave 5.8 g (72.4%) of 3-(2,5-difluorophenyl)-1,4-dimethyl-5-(trifluoromethyl)-1H-pyrazole as an oil; 1HNMR (CDCl3) δ 2.0 (quintet, 3H, J=2.1 Hz), 3.9 (d, 3H, J=1.2 Hz), 6.9-7.1 (m, 3H). Anal. Calcd for C13H9F5N2: C, 52.18; H, 3.28; N, 10.14. Found: C, 52.20; H, 3.30; N, 10.11.

後処理

  1. customto exceed -70° C
  2. stirringAfter stirring for 5 minutes
  3. customThe cooling bath was removed
  4. additionThe solution was diluted with diethyl ether
  5. washthe combined organic extracts were washed twice with brine
  6. dry with materialdried over anhydrous magnesium sulfate and concd in vacuo
  7. customChromatographic purification (silica, 5% ethyl acetate in hexanes)

出典と根拠

ORDレコード
ord-3e9ef4cf57294a5a9fc0b5fd42fda641
出典データセット
uspto-grants-1997_09
特許番号
US05668088

反応ノート

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