Toluene → Methyl (2s)-2-ethyl-2,3-dihydro-1-benzofuran-2-carboxylate

HRID 2113156ノート

反応式

HRID 2113156 の反応式
F[C:2]1[CH:15]=[CH:14][CH:13]=[CH:12][C:3]=1[CH2:4][C@@:5]([OH:11])([CH2:9][CH3:10])[C:6]([OH:8])=[O:7].[CH3:16]N(C=O)C.C1(C)C=CC=CC=1.[H-].[Na+]>O>[CH2:9]([C@@:5]1([C:6]([O:8][CH3:16])=[O:7])[CH2:4][C:3]2[CH:12]=[CH:13][CH:14]=[CH:15][C:2]=2[O:11]1)[CH3:10]

参加物

6

反応物 4

HCID 1140TolueneHCID 6228DimethylformamideHCID 24758Sodium hydrideHCID 11171855(2S)-2-(2-Fluoro-benzyl)-2-hydroxy-butyric acid

生成物 1

HCID 57358441Methyl (2s)-2-ethyl-2,3-dihydro-1-benzofuran-2-carboxylate

試薬・触媒・溶媒 1

HCID 962Water溶媒

反応条件

温度
110 °C

実験手順

To a solution of the acid from step 1 (4.0 g, ca. 20 mmol) in 1:4 DMF:toluene (100 mL.) was added 60% NaH in mineral oil (1.76 g, 44 mmol) in 3 portions. The reaction mixture was stirred at 110° C. under N2 for 4 hrs. The reaction was cooled to room temperature and poured into cold water (100 mL). The aqueous layer was washed with hexane (50 mL), acidified with 2 N aqueous HCl and extracted with ethyl acetate (3×50 mL). The extracts were washed with brine (50 mL), dried and concentrated. The residue was dissolved in 7:1 benzene:MeOH (80 mL) and treated with TMSCHN2 (1M in hexane) until gas evolution ceased. The reaction was concentrated and the residue was chromatographed on silica gel eluting with 85:15 hexane:ethylacetate to give methyl (2S)-2-ethyl-2,3-dihydro-benzofuran-2-carboxylate.

後処理

  1. temperatureThe reaction was cooled to room temperature
  2. washThe aqueous layer was washed with hexane (50 mL)
  3. extractionextracted with ethyl acetate (3×50 mL)
  4. washThe extracts were washed with brine (50 mL)
  5. customdried
  6. concentrationconcentrated
  7. dissolutionThe residue was dissolved in 7:1 benzene
  8. additionMeOH (80 mL) and treated with TMSCHN2 (1M in hexane) until gas evolution
  9. concentrationThe reaction was concentrated
  10. customthe residue was chromatographed on silica gel eluting with 85:15 hexane

出典と根拠

ORDレコード
ord-f792c5cd496448999b4a07e13277c14c
出典データセット
uspto-grants-2009_04
特許番号
US07524882B2

反応ノート

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