2,2-dimethyl-1-oxa-8-azaspiro[4.5]decane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Trifluoroacetic acid (10 ml) was added to a solution of 1,1-dimethylethyl 4-hydroxy-4-(3-hydroxy-3-methylbut-1-yl)-1-piperidinecarboxylate (from step (iv) above; 3.9 g, 13.57 mmol) in dichloromethane (10 ml) and the mixture was stirred at room temperature overnight. The solvent was evaporated under reduced pressure and the residue was purified by flash column chromatography on silica gel, eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1) to give the title compound (2.04 g, 89%). The solvent was evaporated under reduced pressure the residue was purified by flash column chromatography on silica gel eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Trifluoroacetic acid (10 mL) was added to a solution of 1,1-dimethylethyl 4-hydroxy-4-(3-hydroxy-3-methylbut-1-yl)-1-piperidinecarboxylate (Description 80, 3.9 g, 13.57 mmol) in dichloromethane (10 mL) and the mixture was stirred at room temperature overnight. The solvent was evaporated under reduced pressure and the residue was purified by flash column chromatography on silica gel, eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1) to give the title compound (2.04 g, 89%). m/z (ES+) 170 (M+1). The solvent was evaporated under reduced pressure the residue was purified by flash column chromatography on silica gel eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Trifluoroacetic acid (10 mL) was added to a solution of 1,1-dimethylethyl 4-hydroxy-4-(3-hydroxy-3-methylbut-1-yl)-1-piperidinecarboxylate (Description 80, 3.9 g, 13.57 mmol) in dichloromethane (10 mL) and the mixture was stirred at room temperature overnight. The solvent was evaporated under reduced pressure and the residue was purified by flash column chromatography on silica gel, eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1) to give the title compound (2.04 g, 89%). m/z (ES+) 170 (M+1). The solvent was evaporated under reduced pressure the residue was purified by flash column chromatography on silica gel eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Trifluoroacetic acid (10 mL) was added to a solution of 1,1-dimethylethyl 4-hydroxy-4-(3-hydroxy-3-methylbut-1-yl)-1-piperidinecarboxylate (Description 80, 3.9 g, 13.57 mmol) in dichloromethane (10 mL) and the mixture was stirred at room temperature overnight. The solvent was evaporated under reduced pressure and the residue was purified by flash column chromatography on silica gel, eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1) to give the title compound (2.04 g, 89%). m/z (ES+) 170 (M+1). The solvent was evaporated under reduced pressure the residue was purified by flash column chromatography on silica gel eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Trifluoroacetic acid (10 ml) was added to a solution of 1,1-dimethylethyl 4-hydroxy-4-(3-hydroxy-3-methylbut-1-yl)-1-piperidinecarboxylate (from step (iv) above; 3.9 g, 13.57 mmol) in dichloromethane (10 ml) and the mixture was stirred at room temperature overnight. The solvent was evaporated under reduced pressure and the residue was purified by flash column chromatography on silica gel, eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1) to give the title compound (2.04 g, 89%). The solvent was evaporated under reduced pressure the residue was purified by flash column chromatography on silica gel eluting with CH2Cl2/MeOH/NH3(Aq.) (90:10:1)