Sodium Carbonate → 2-t-Butyldimethylsilyl-3-(t-butyldimethylsilyloxymethylene)-6-methoxy-benzofuran

HRID 1020469Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 1020469
I[C:2]1[CH:7]=[CH:6][C:5]([O:8][CH3:9])=[CH:4][C:3]=1[OH:10].[Si:11]([C:18]#[C:19][CH2:20][O:21][Si:22]([C:25]([CH3:28])([CH3:27])[CH3:26])([CH3:24])[CH3:23])([C:14]([CH3:17])([CH3:16])[CH3:15])([CH3:13])[CH3:12].[Cl-].[Li+].C(=O)([O-])[O-].[Na+].[Na+]>CN(C)C=O.C([O-])(=O)C.[Pd+2].C([O-])(=O)C>[Si:11]([CH:18]1[C:19](=[CH:20][O:21][Si:22]([C:25]([CH3:28])([CH3:27])[CH3:26])([CH3:23])[CH3:24])[C:2]2[CH:7]=[CH:6][C:5]([O:8][CH3:9])=[CH:4][C:3]=2[O:10]1)([C:14]([CH3:17])([CH3:16])[CH3:15])([CH3:13])[CH3:12]

Komponenten

7

Edukt 4

HCID 10340Sodium CarbonateHCID 433294Lithium ChlorideHCID 10968062Tert-butyl(3-(tert-butyldimethylsilyl)prop-2-ynyloxy)-dimethylsilaneHCID 114140152-Iodo-5-methoxyphenol

Produkt 1

HCID 672878412-t-Butyldimethylsilyl-3-(t-butyldimethylsilyloxymethylene)-6-methoxy-benzofuranAusbeute 87 %

Reagenzien, Katalysatoren, Lösungsmittel 2

HCID 167845palladium(II) acetateKatalysatorHCID 6228DimethylformamideLösungsmittel

Versuchsvorschrift

A suspension of 2-iodo-5-methoxyphenol (1.1 g, 4.41 mmol), 1-(tert-butyldimethylsilyl)-3-(tert-butyldimethylsilyloxy)propyne (1.5 g, 5.28 mmol), lithium chloride (189 mg, 4.45 mmol) and sodium carbonate (2.34 g, 22.08 mmol) in dry dimethylformamide (5 mL) at 100° C. was deoxygenated 4 times by evacuation and backfilling with nitrogen. Palladium acetate (135 mg, 0.60 mmol) was added and the reaction vessel was degassed twice with nitrogen. The reaction mixture was then stirred at this temperature for 4 hours (monitored by tlc) and the solvent was removed by distillation under vacuum. The residue was dissolved in ethyl acetate (75 mL), stirred well, filtered and treated with triethylamine (5 mL). The solution was concentrated onto silica gel (10 g) and purified by flash chromatography (silica gel, eluent=hexane/diethyl ether/triethylamine; 95:5:1%) to give the title compound as a yellow oil (1.09 g, 87%); 1H NMR (300 MHz, CDCl3) δ 7.52 (d, 1H, J=8.57 Hz), 6.97 (d, 1H, J=2.15 Hz), 6.83 (dd, 1H, J=8.54, 2.18 Hz), 4.81 (s, 2H, CH2), 3.83 (s, 3H, OMe), 0.93 (s, 9H), 0.91 (s, 9H), 0.34 (s, 6H), 0.11 (s, 6H).

Aufarbeitung

  1. customwas deoxygenated 4 times by evacuation and backfilling with nitrogen
  2. customthe reaction vessel was degassed twice with nitrogen
  3. customthe solvent was removed by distillation under vacuum
  4. dissolutionThe residue was dissolved in ethyl acetate (75 mL)
  5. stirringstirred well
  6. filtrationfiltered
  7. additiontreated with triethylamine (5 mL)
  8. concentrationThe solution was concentrated onto silica gel (10 g)
  9. custompurified by flash chromatography (silica gel, eluent=hexane/diethyl ether/triethylamine; 95:5:1%)

Quellen und Nachweise

ORD-Eintrag
ord-7ce0cd4c04e447379eb967cf2f4ebcc4
Quelldatensatz
uspto-grants-2014_05
Patentnummer
US08716335B2

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