Reaktion #2008425

Reaktionsgleichung

6-Methoxy-1-tetralone

NaH

Diethyl carbonate

NaH THF

→

crude brown oil

Ausbeute 106.5%

6-Methoxy-1-oxo-1,2,3,4-tetrahydronaphthalene-2-carboxylic acid ethyl ester

Ausbeute 106.5%

Lösungsmittel

THF

THF

—

hexanes

THF

Et2O

AcOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigedried 3 neck round-bottomed flask
2. 2
   Temperaturthe slurry was heated
3. 3
   Temperaturat reflux under N2
4. 4
   Temperaturat reflux
5. 5
   TemperaturThe reaction mixture was then heated
6. 6
   Temperaturat reflux for 2 days
7. 7
   Waschenthe organic layer was washed with saturated NaCl solution (5×25 mL)
8. 8
   Trocknendried (MgSO4)
9. 9
   Einengenconcentrated under reduced pressure

Vorschrift

NaH (3.4 g, 60% in mineral oil, 83.3 mmol) was washed with hexanes (3×70 mL) and THF (1×30 mL) in an oven dried 3 neck round-bottomed flask. Diethyl carbonate (5.5 mL, 45.4 mmol) was added to the NaH/THF suspension in anhydrous THF (20 mL) and the slurry was heated at reflux under N2. 6-Methoxy-1-tetralone (4 g, 22.7 mmol) in THF (40 mL) was added dropwise via an addition funnel to the suspension at reflux. The reaction mixture was then heated at reflux for 2 days. The solution was cooled to room temperature and glacial AcOH (3.6 mL) was added in a dropwise manner. Et2O (150 mL) was then added and the organic layer was washed with saturated NaCl solution (5×25 mL), dried (MgSO4), and concentrated under reduced pressure to provide a crude brown oil (6.0 g). The oil was subjected to medium pressure chromatography on silica (CHCl3) to provide a dark oil which solidified upon standing (5.17 g, 91.8% yield). The solid was recrystallized from EtOAc/hexane to provide a white solid. mp 58-60° C. 1H-NMR (300 MHz, CDCl3) δ 1.27-1.36 (t, 3H), 2.20-3.56 (m, 5H), 3.85 (s, 3H), 4.23-4.28 (m, 2H), 6.70 (s, 1H), 6.77-6.85 (d, 1H), 7.72-8.03 (d, 1H).

Quelle