tert-butyl 4-hydroxy-1-oxa-8-azaspiro[4.5]decane-8-carboxylate

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

Procedure: tert-Butyl 4-hydroxy-1-oxa-8-azaspiro[4.5]decane-8-carboxylate (from step (iii) above; 300 mg) was dissolved in dichloromethane and trifluoroacetic acid (2 mL) was added. The solution was stirred for 2 h and was concentrated in vacuo to afford the product as a colorless oil. was concentrated in vacuo

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

Procedure: tert-Butyl 4-(1,3-dihydroxypropyl)-4-hydroxypiperidine-1-carboxylate (from step (ii) above; 480 mg) was dissolved in dichloromethane and p-toluenesulfonyl chloride was added followed by triethylamine (0.49 mL) and the mixture was stirred for 12 h. An additional aliquot of triethylamine was added (0.49 mL) and the mixture stirred for 48 h. This mixture was concentrated in vacuo. The crude product was purified by chromatography on silica using 50-95% ethyl acetate in iso-hexane as eluant to afford the product (300 mg). the mixture stirred for 48 h This mixture was concentrated in vacuo The crude product was purified by chromatography on silica using 50-95% ethyl acetate in iso-hexane as eluant

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

Procedure: tert-Butyl 4-hydroxy-1-oxa-8-azaspiro[4.5]decane-8-carboxylate (from step (iii) above; 300 mg) was dissolved in dichloromethane and trifluoroacetic acid (2 mL) was added. The solution was stirred for 2 h and was concentrated in vacuo to afford the product as a colorless oil. was concentrated in vacuo

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

Procedure: tert-Butyl 4-(1,3-dihydroxypropyl)-4-hydroxypiperidine-1-carboxylate (from step (ii) above; 480 mg) was dissolved in dichloromethane and p-toluenesulfonyl chloride was added followed by triethylamine (0.49 mL) and the mixture was stirred for 12 h. An additional aliquot of triethylamine was added (0.49 mL) and the mixture stirred for 48 h. This mixture was concentrated in vacuo. The crude product was purified by chromatography on silica using 50-95% ethyl acetate in iso-hexane as eluant to afford the product (300 mg). the mixture stirred for 48 h This mixture was concentrated in vacuo The crude product was purified by chromatography on silica using 50-95% ethyl acetate in iso-hexane as eluant