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

HRID 1481518ノート

反応式

HRID 1481518 の反応式
[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]

参加物

4

反応物 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

生成物 1

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

試薬・触媒・溶媒 1

HCID 1140Toluene溶媒

反応条件

温度
110 °C

実験手順

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).

後処理

  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

出典と根拠

ORDレコード
ord-b009a73e84644b1989cbeb8c078624fd
出典データセット
uspto-grants-2016_08
特許番号
US09409915B2

反応ノート

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