2-Oxa-9-azaspiro[5.5]undecane (9CI) synthesis

Yield: 100%

Reaction Conditions:

with acetyl chloride in methanol at 0 - 20; for 3 h;

Steps:

139 Description 139 [0553] 2-Oxa-9-azaspiro[5,5]undecane
Acetyl chloride (1 mL) was added to stirred, cooled (0° C.) methanol (10 mL) and the mixture was stirred at 0° C. for 5 minutes. 1,1-Dimethylethyl 2-oxa-9-azaspiro[5,5]undecane-9-carboxylate (Description 138, 78 mg, 0.27 mmol) was added and the mixture was stirred at room temperature for 3 hours. The solvent was evaporated under reduced pressure, aqueous sodium carbonate (10%, 10 mL) was added and the mixture was extracted with dichloromethane (3×10 mL). The combined organic fractions were dried (Na2SO4) and the solvent was evaporated under reduced pressure to give the title compound (50 mg, 100%). m/z (ES+) 156 (M+1).

References:

Castro Pineiro, Jose Luis;Dinnell, Kevin;Elliott, Jason Matthew;Hollingworth, Gregory John;Shaw, Duncan Edward;Swain, Christopher John US2003/236250, 2003, A1 Location in patent:Page 139