Reaktion #162296

Reaktionsgleichung

azepan-2-one

trimethyloxonium tetrafluoroborate

→

(E)-7-methoxy-3,4,5,6-tetrahydro-2H-azepine

Ausbeute 95.0%

Lösungsmittel

DCM

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe reaction was quenched by the addition of saturated aqueous NaHCO3 (5 ml) (caution: vigorous CO2 evolution)
2. 2
   workup.ADDITIONMore aqueous sodium hydrogen carbonate was added until the aqueous layer
3. 3
   SonstigeThe organic layer was removed
4. 4
   Extraktionthe aqueous layer extracted with DCM (5 mL)
5. 5
   TrocknenCombined organic layers were dried over anhydrous sodium sulfate
6. 6
   Filtrationfiltered
7. 7
   Sonstigeevaporated under reduced pressure

Vorschrift

To a solution of azepan-2-one (1.13 g, 10.0 mmol) in DCM (10 mL) in a 40 mL screw cap vial was added freshly prepared trimethyloxonium tetrafluoroborate (1.57 g, 10.59 mmol). The resulting suspension was shaken overnight. The reaction was quenched by the addition of saturated aqueous NaHCO3 (5 ml) (caution: vigorous CO2 evolution). More aqueous sodium hydrogen carbonate was added until the aqueous layer reached pH 8. The organic layer was removed and the aqueous layer extracted with DCM (5 mL). Combined organic layers were dried over anhydrous sodium sulfate, filtered and evaporated under reduced pressure to yield (E)-7-methoxy-3,4,5,6-tetrahydro-2H-azepine (1.2 g, 95%) as a clear oil. LCMS (+ESI) m/z 128.2 [M+H]+. 1H-NMR (CDCl3) δ 3.60 (s, 3H), 3.45 (m, 2H), 2.40 (m, 2H), 1.80 (m, 2H), 1.60-1.50 (m, 4H).

Quelle