Tetrahydrofuran → 5-Isopropenyl-2,4-dimethoxy-benzoic acid methyl ester

HRID 424103

反応式

HRID 424103 の反応式
[CH3:1][O:2][C:3](=[O:15])[C:4]1[CH:9]=[C:8](Br)[C:7]([O:11][CH3:12])=[CH:6][C:5]=1[O:13][CH3:14].C([O-])([O-])=O.[Cs+].[Cs+].[CH2:22]1[CH2:26]OC[CH2:23]1>O.CCOC(C)=O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[CH3:1][O:2][C:3](=[O:15])[C:4]1[CH:9]=[C:8]([C:22]([CH3:26])=[CH2:23])[C:7]([O:11][CH3:12])=[CH:6][C:5]=1[O:13][CH3:14]

参加物

7

実験手順

To potassium isopropylidene trifluoroborate (4.87 g, 32.7 mmol) and 5-bromo-2,4-dimethoxybenzoic acid methyl ester (7.5 g, 27.3 mmol) in THF (195 ml) was added Cs2CO3 (26.6 g, 81.8 mmol) in water (39 ml). The reaction was degassed and Pd(PPh3)4 (1.58 g, 1.36 mmol) added. The reaction was heated at reflux for three days then quenched by adding water and extracted with EtOAc (×2). The combined organic layers were washed with brine, dried (MgSO4), filtered and evaporated to leave an orange solid. The product was taken up in EtOAc again and the precipitate filtered. The filtrate was evaporated to dryness to yield 5-isopropenyl-2,4-dimethoxy-benzoic acid methyl ester (6.2 g). 1H NMR (Me-d3-OD) 7.68 (1H, s), 6.66 (1H, s), 5.10-5.08 (1H, m), 5.02-5.00 (1H, m), 3.93 (3H, s), 3.92 (3H, s), 3.84 (3H, s), 2.08-2.06 (3H, m). MS: [M+H]+ 237.

後処理

  1. customThe reaction was degassed
  2. temperatureThe reaction was heated
  3. temperatureat reflux for three days
  4. customthen quenched
  5. additionby adding water
  6. extractionextracted with EtOAc (×2)
  7. washThe combined organic layers were washed with brine
  8. dry with materialdried (MgSO4)
  9. filtrationfiltered
  10. customevaporated
  11. customto leave an orange solid
  12. filtrationthe precipitate filtered
  13. customThe filtrate was evaporated to dryness

出典と根拠

ORDレコード
ord-08a9916e00dd4ab2bdb830d9bb8bc2c7
出典データセット
uspto-grants-2012_01
特許番号
US08101648B2

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