Methanol → Methyl 2,4-bis-benzyloxy-5-isopropenylbenzoate

HRID 334879Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 334879
[CH2:1]([Li])[CH2:2][CH2:3][CH3:4].[C:6]([C:9]1[C:10]([O:27][CH2:28][C:29]2[CH:34]=[CH:33][CH:32]=[CH:31][CH:30]=2)=[CH:11][C:12]([O:19]CC2C=CC=CC=2)=[C:13]([CH:18]=1)[C:14]([O:16][CH3:17])=[O:15])(=O)[CH3:7].[CH3:35]O.O1C[CH2:40][CH2:39][CH2:38]1>[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[CH2:1]([O:19][C:12]1[CH:11]=[C:10]([O:27][CH2:28][C:29]2[CH:34]=[CH:33][CH:32]=[CH:31][CH:30]=2)[C:9]([C:6]([CH3:35])=[CH2:7])=[CH:18][C:13]=1[C:14]([O:16][CH3:17])=[O:15])[C:2]1[CH:40]=[CH:39][CH:38]=[CH:4][CH:3]=1

Komponenten

6

Edukt 4

HCID 887MethanolHCID 8028Tetrahydrofuran2×HCID 11955869HCID 11955869, VerbindungHCID 178418339Butyllithium

Produkt 1

HCID 11955870Methyl 2,4-bis-benzyloxy-5-isopropenylbenzoateAusbeute 36 %

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 74505Methyltriphenyliphosphonium bromideKatalysator

Reaktionsbedingungen

Temperatur
0 °C

Versuchsvorschrift

A stirred suspension of methyltriphenylphosphonium bromide (1.96 g, 5.5 mmol) in anhydrous tetrahydrofuran (20 ml) at 0° C. under a nitrogen atmosphere was treated dropwise with n-butyl lithium (1.6 M in hexanes, 3.5 ml, 5.5 mmol) and the resulting bright yellow solution was stirred at 0° C. for 30 minutes. A solution of methyl 5-acetyl-2,4-bis-benzyloxybenzoate (1.95 g, 5.00 mmol) in anhydrous tetrahydrofuran (20 ml) was added dropwise and the resulting mixture was allowed to warm to room temperature and was stirred for 16 hours. Methanol (10 ml) was added and the solvent was removed in vacuo. The residues were partitioned between dichloromethane and water, the organic layer was separated and the solvent removed in vacuo to afford a brown gum that was purified by column chromatography on silica. Elution with 7% ethyl acetate in petroleum ether afforded methyl 2,4-bis-benzyloxy-5-isopropenyl-benzoate as a colourless solid (700 mg, 36%). 1H NMR (DMSO-d6) 7.59 (1H, s), 7.52 (2H, d), 7.64-7.32 (8H, m), 6.97 (1H, s), 5.28 (2H, s), 5.22 (2H, s), 5.09 (1H, s), 5.04 (1H, s), 3.76 (3H, s), 2.02 (3H, s). MS: [M+H]+ 389.

Aufarbeitung

  1. temperatureto warm to room temperature
  2. stirringwas stirred for 16 hours
  3. customthe solvent was removed in vacuo
  4. customThe residues were partitioned between dichloromethane and water
  5. customthe organic layer was separated
  6. customthe solvent removed in vacuo
  7. customto afford a brown gum that
  8. customwas purified by column chromatography on silica
  9. washElution with 7% ethyl acetate in petroleum ether

Quellen und Nachweise

ORD-Eintrag
ord-653499ddc9c342b08bdd5819d1377dec
Quelldatensatz
uspto-grants-2014_11
Patentnummer
US08883790B2

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