Azobisisobutyronitrile → 4-bromo-6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran

HRID 275423

反応式

HRID 275423 の反応式
[C:1]([C:3]1[CH:4]=[CH:5][C:6]2[O:11][C:10]([CH3:13])([CH3:12])[CH2:9][CH2:8][C:7]=2[CH:14]=1)#[N:2].[Br:15]N1C(=O)CCC1=O.N(C(C)(C)C#N)=NC(C)(C)C#N>C(Cl)(Cl)(Cl)Cl>[Br:15][CH:8]1[C:7]2[CH:14]=[C:3]([C:1]#[N:2])[CH:4]=[CH:5][C:6]=2[O:11][C:10]([CH3:12])([CH3:13])[CH2:9]1

参加物

5

反応物 3

HCID 6547AzobisisobutyronitrileHCID 67184N-bromobutanimideHCID 109212656-Cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran

生成物 1

HCID 102446284-bromo-6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran収率 79%

試薬・触媒・溶媒 1

HCID 5943Carbon Tetrachloride溶媒2 回

実験手順

To a solution of 6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran (6.40 g, 34.18 mmoles), title A compound, in carbon tetrachloride (90 mL) was added N-bromosuccinimide (6.69 g, 37.6 mmoles). The solution was purged with argon. A solution of Azobisisobutyronitrile (0.4 g, 3.42 mmoles) in carbon tetrachloride (10 mL) was added; the reaction was heated at reflux for 30 minutes with irradiation (high intensity visible light). The reaction mixture was concentrated under vacuum and the residue was dissolved in 75 mL ethyl acetate. The solution was washed successively with distilled water (4×75 mL), saturated sodium bicarbonate solution (75 mL), saturated NaCl solution (75 mL), and dried over magnesium sulfate. The solvent was recovered under vacuum to obtain an orange waxy solid which was triturated with cold pentane to provide a beige solid (7.19g). This was crystallized from ethyl acetate and hexanes (10:90) to yield the title compound (4.60 g) as off-white needles, m.p. 94°-95° C. The mother liquors were combined and chromatographed on silica gel eluting with hexane/ethyl acetate (19:1) to afford additional product (2.26 g) for a combined yield of 75.4%. Microanalysis calculated for C12H12NOBr: C, 54.16; H, 4.54; N, 5.26; Br, 30.02. Found: C, 54.55; H, 4.62; N, 5.46; Br, 29.86

後処理

  1. customThe solution was purged with argon
  2. temperaturethe reaction was heated
  3. temperatureat reflux for 30 minutes with irradiation (high intensity visible light)
  4. concentrationThe reaction mixture was concentrated under vacuum
  5. dissolutionthe residue was dissolved in 75 mL ethyl acetate
  6. washThe solution was washed successively with distilled water (4×75 mL), saturated sodium bicarbonate solution (75 mL), saturated NaCl solution (75 mL)
  7. dry with materialdried over magnesium sulfate
  8. customThe solvent was recovered under vacuum
  9. customto obtain an orange waxy solid which
  10. customwas triturated with cold pentane

出典と根拠

ORDレコード
ord-9cab69c4365a45e887403c9da6fff74f
出典データセット
uspto-grants-1995_02
特許番号
US05393771

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