Water → Tert-butyl 4-oxo-1-oxa-9-azaspiro(5.5)undecane-9-carboxylate

Participants

Reaction Steps

To a solution of Compound 29a (1.6 g, 5.99 mmol) in a mixture of dioxane-water (32.9 mL and 11 mL respectively) under stirring at r.t. was added a 4% sol. of osmium tetroxide in water (0.762 μL, 0.125 mmol). After 2 h, was added portionwise milled sodium metaperiodate (2.56 g, 12 mmol) affording a suspension that tended to become clear gray from brownish. After 4 h H2O was added, extracting with EtOAc, washing with H2O, drying over Na2SO4, evaporating the solvent to dryness. The residual tawny semi-solid was purified by means of automated flash chromatography (SP1®TM-Biotage; Petroleum Ether-EtOAc 7:3) to give 0.96 g of the title compound as a grey solid. Yield: 59.5%

Provenance & Evidence