2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → 3-Tert-butyl-4-cyano-isoxazole-5-carboxylic acid ethyl ester

HRID 570198노트

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HRID 570198 반응식
[CH2:1]([O:3][C:4]([CH:6]1[O:10][N:9]=[C:8]([C:11]([CH3:14])([CH3:13])[CH3:12])[CH:7]1[C:15]#[N:16])=[O:5])[CH3:2].C(C1C(=O)C(Cl)=C(Cl)C(=O)C=1C#N)#N>C1(C)C=CC=CC=1>[CH2:1]([O:3][C:4]([C:6]1[O:10][N:9]=[C:8]([C:11]([CH3:13])([CH3:12])[CH3:14])[C:7]=1[C:15]#[N:16])=[O:5])[CH3:2]

참가 물질

4

반응물 2

HCID 67752,3-Dichloro-5,6-dicyano-1,4-benzoquinoneHCID 674117013-tert-Butyl-4-cyano-4,5-dihydro-isoxazole-5-carboxylic acid ethyl ester

생성물 1

HCID 674115853-Tert-butyl-4-cyano-isoxazole-5-carboxylic acid ethyl ester

시약·촉매·용매 1

HCID 1140Toluene용매

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온도
110 °C

실험 절차

3-tert-Butyl-4-cyano-4,5-dihydro-isoxazole-5-carboxylic acid ethyl ester (1.51 g, 2.56 mmol corrected for the measured purity, prepared as described in the previous step) was dissolved in toluene (10 mL) and DDQ (2.41 g, 10.6 mmol) was added as a solid. The resulting mixture was heated to 110° C. for 16 h and then cooled to room temperature and diluted with hexanes (2 mL). The resulting suspension was filtered and the precipitate was washed once with toluene (4 mL). The filtrates were combined and concentrated under reduced pressure. The resulting residue was chromatographed on a 24-g SiO2 pre-packed column eluting with 0:1-1:4 EtOAc-hexanes to yield 3-tert-butyl-4-cyano-isoxazole-5-carboxylic acid ethyl ester. 1H-NMR (400 MHz, CDCl3) δ: 4.52 (q, J=7.1 Hz, 2H), 1.49 (s, 9H), 1.43-1.48 (t, J=7.1 Hz, 3H).

후처리

  1. customprepared
  2. temperaturecooled to room temperature
  3. filtrationThe resulting suspension was filtered
  4. washthe precipitate was washed once with toluene (4 mL)
  5. concentrationconcentrated under reduced pressure
  6. customThe resulting residue was chromatographed on a 24-g SiO2 pre-packed column
  7. washeluting with 0:1-1:4 EtOAc-hexanes

출처 및 근거

ORD 기록
ord-4771b36d99a740d1847d928a81d205d0
출처 데이터셋
uspto-grants-2015_05
특허 번호
US09023846B2

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