Reacción #162296

Ecuación de reacción

azepan-2-one

trimethyloxonium tetrafluoroborate

→

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

Rendimiento 95.0%

Disolventes

DCM

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe 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
   OtroThe organic layer was removed
4. 4
   Extracciónthe aqueous layer extracted with DCM (5 mL)
5. 5
   SecadoCombined organic layers were dried over anhydrous sodium sulfate
6. 6
   Filtraciónfiltered
7. 7
   Otroevaporated under reduced pressure

Procedimiento

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).

Fuente