Reaktion #79349

Reaktionsgleichung

ethyl 7-hydroxychromane-2-carboxylate

benzyl 3-bromopropyl ether

potassium carbonate

→

title compound

Ausbeute 66.0%

Ethyl 7-(3-benzyloxypropoxy)-chromane-2-carboxylate

Ausbeute 66.0%

Lösungsmittel

acetone

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe resulting suspension was heated
2. 2
   Temperaturto reflux overnight
3. 3
   SonstigeAcetone was removed under reduced pressure
4. 4
   workup.ADDITIONdiluted with AcOEt and sat. NH4Claq
5. 5
   SonstigeThe organic layer was separated
6. 6
   Extraktionthe aqueous layer was extracted twice with AcOEt
7. 7
   TrocknenThe combined organic layers were dried over anhydrous Na2SO4
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated
10. 10
    Sonstigechromatographed on silica gel eluting with 10% AcOEt/hexanes

Vorschrift

To a 200 ml acetone solution of ethyl 7-hydroxychromane-2-carboxylate (9.18 g, 41.3 mmol) was added benzyl 3-bromopropyl ether (14.2 g, 62.0 mmol), powdered potassium carbonate (11.4 g, 82.5 mmol), and tetrabutylammonium iodide (1.53 g, 4 mmol). The resulting suspension was heated to reflux overnight. Acetone was removed under reduced pressure, diluted with AcOEt and sat. NH4Claq. The organic layer was separated, and the aqueous layer was extracted twice with AcOEt. The combined organic layers were dried over anhydrous Na2SO4, filtered, concentrated, and chromatographed on silica gel eluting with 10% AcOEt/hexanes to give the title compound 10.1 g (66%).

Quelle