Bromine → HCID 86691330、化合物

HRID 1477262ノート

反応式

HRID 1477262 の反応式
[F:1][C:2]1[CH:12]=[CH:11][CH:10]=[C:9]([F:13])[C:3]=1/[CH:4]=[CH:5]/C(O)=O.[Br:14]Br>ClCCl>[Br:14]/[CH:5]=[CH:4]\[C:3]1[C:2]([F:1])=[CH:12][CH:11]=[CH:10][C:9]=1[F:13]

参加物

4

反応物 2

HCID 24408BromineHCID 53722672,6-Difluorocinnamic acid

生成物 1

HCID 86691330HCID 86691330、化合物

試薬・触媒・溶媒 1

HCID 6344Dichloromethane溶媒

反応条件

温度
0 °C

実験手順

To a stirred suspension of E-2,6-difluorocinnamic acid (2.0 g, 11 mmol) in dichloromethane at 0° C. is added bromine (0.56 mL, 11 mmol) dropwise. The mixture is stirred overnight as it is slowly allowed to reach temperature. Evaporation of the volatiles under reduced pressure affords the crude dibrominated carboxylic acid intermediate that is directly carried to the next step without further purification. To the crude solid is added DMF (20 mL) and a small crystal of BHT. The mixture is cooled to 0° C., and triethylamine (3 mL) is added. The mixture is stirred overnight as it is slowly allowed to reach temperature. Contents are poured in 2N aqueous HCl, extracted with diethyl ether, and the combined organic fractions are washed with saturated aqueous NaCl. Evaporation of the volatiles yields a crude product that is further purified by passing on a SiO2 plug using pentane as an eluent. Evaporation of the solvents under reduced pressure affords bromoalkene 11q as a colorless oil (1.35 g, 57%, ≧20:1 d.r. by 19F-NMR). 1H-NMR (CDCl3, 300 MHz): δ=7.42-7.32 (m, 1H), 7.07 (d, J=7.9 Hz, 1H), 7.05-6.95 (m, 2H), 6.84 (d, J=7.9 Hz, 1H). 13C-NMR (CDCl3, 75 MHz): δ=159.9 (dd, J=250, 7 Hz), 130.0 (t, J=10 Hz), 122.3, 114.8, 130.0 (t, J=20 Hz), 111.5 (dd, J=18, 7 Hz). 19F-NMR (CDCl3, 282 MHz): δ=−108.5. HR-MS (EI): Calcd. for C8H5F2Br [M+]: 217.9543. found 217.9538.

後処理

  1. customEvaporation of the volatiles under reduced pressure
  2. customaffords the crude dibrominated carboxylic acid intermediate that
  3. customis directly carried to the next step without further purification
  4. additionTo the crude solid is added DMF (20 mL)
  5. additiontriethylamine (3 mL) is added
  6. stirringThe mixture is stirred overnight as it
  7. additionContents are poured in 2N aqueous HCl
  8. extractionextracted with diethyl ether
  9. washthe combined organic fractions are washed with saturated aqueous NaCl
  10. customEvaporation of the volatiles
  11. customyields a crude product that
  12. customis further purified
  13. customEvaporation of the solvents under reduced pressure

出典と根拠

ORDレコード
ord-796e1764fbfb4bada78658997a41686a
出典データセット
uspto-grants-2016_08
特許番号
US09403781B2

反応ノート

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