2-Methyl-4-nitro-pyrazole-3-carbaldehyde → 5-(5,6-dimethyl-4-((triethylsilyl)oxy)-3,6-dihydro-2H-pyran-2-yl)-1-methyl-4-nitro-1H-pyrazole

HRID 521879

反応式

HRID 521879 の反応式
[CH3:1][N:2]1[C:6]([CH:7]=[O:8])=[C:5]([N+:9]([O-:11])=[O:10])[CH:4]=[N:3]1.[CH2:12]([Si:14]([CH2:24][CH3:25])([CH2:22][CH3:23])[O:15][C:16](/[C:18](/[CH3:21])=[CH:19]/[CH3:20])=[CH2:17])[CH3:13]>>[CH3:21][C:18]1[CH:19]([CH3:20])[O:8][CH:7]([C:6]2[N:2]([CH3:1])[N:3]=[CH:4][C:5]=2[N+:9]([O-:11])=[O:10])[CH2:17][C:16]=1[O:15][Si:14]([CH2:22][CH3:23])([CH2:12][CH3:13])[CH2:24][CH3:25]

参加物

3

反応物 2

HCID 598129402-Methyl-4-nitro-pyrazole-3-carbaldehyde2 回HCID 86713828(E)-triethyl((3-methylpenta-1,3-dien-2-yl)oxy)silane

生成物 1

HCID 867138275-(5,6-dimethyl-4-((triethylsilyl)oxy)-3,6-dihydro-2H-pyran-2-yl)-1-methyl-4-nitro-1H-pyrazole

反応条件

温度
65 °C

実験手順

To a solution of (E)-3-methylpent-3-en-2-one (2.69 mL, 24.1 mmol) in DCM (200 mL) cooled to 0° C. was added Et3N (10.5 mL, 79.5 mmol) followed by TESOTf (6.0 mL, 26.5 mmol). The mixture was warmed to room temperature and stirred for 18 hr. Saturated aqueous NaHCO3 solution (100 mL) and DCM (200 mL) were added. The aqueous layer was extracted with DCM (3×200 mL) and the combined organic layers were washed with brine (100 mL), separated, dried over MgSO4 and concentrated under reduced pressure to give (E)-triethyl((3-methylpenta-1,3-dien-2-yl)oxy)silane. To a solution of 2-methyl-4-nitro-pyrazole-3-carbaldehyde (1.0 g, 8 mmol, intermediate 3) in CDCl3 (28 mL) was added (E)-triethyl((3-methylpenta-1,3-dien-2-yl)oxy)silane (1.6 g, 7.55 mmol) followed by EuFOD (220 mg, 0.50 mmol). The reaction mixture was heated at 65° C. behind a blast shield for 18 hr in a pressure tube. The mixture was cooled to room temperature and concentrated under reduced pressure. Purification via silica gel column chromatography (0-100% EtOAc/isohexane) gave 5-(5,6-dimethyl-4-((triethylsilyl)oxy)-3,6-dihydro-2H-pyran-2-yl)-1-methyl-4-nitro-1H-pyrazole as a colourless oil (2.92 g, quantitative). 1H NMR (400 MHz, CDCl3) δ 8.07 (s, 1H), 5.64 (dd, J=10.9, 3.6 Hz, 1H), 4.33-4.28 (m, 1H), 4.25-3.94 (m, 3H), 2.50-2.41 (m, 1H), 2.31 (m, 1H), 1.61 (s, 3H), 1.31 (d, J=6.4 Hz, 3H), 1.05-0.97 (m, 6H), 0.73-0.61 (m, 9H).

後処理

  1. temperatureThe mixture was cooled to room temperature
  2. concentrationconcentrated under reduced pressure
  3. customPurification via silica gel column chromatography (0-100% EtOAc/isohexane)

出典と根拠

ORDレコード
ord-349a5570d75e4d5d9532ed78fe145c25
出典データセット
uspto-grants-2016_05
特許番号
US09328106B2

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