Acetic Anhydride → 3-(2-Benzyloxyethyl)-2,4-dioxo-3,9-diaza-bicyclo[3.3.1]nonane-9-carboxylic Acid Benzyl Ester

Participants

Reaction Steps

2,4-Dioxo-3-oxa-9-aza-bicyclo[3.3.1]nonane-9-carboxylic acid benzyl ester (Compound 2, 1.02 g, 3.52 mmol) was dissolved in dioxane (5 mL), and 2-benzyloxyethylamine (0.50 g, 3.32 mmol) was added from the top. The mixture was stirred at room temperature for 1 hour (hr). Then, acetic anhydride (0.62 mL, 6.64 mmol) was added, and the reaction was refluxed for 5 hours. Dioxane was evaporated, and flash chromatographic purification of the residue (20% EtOAc/hexanes) gave Compound 3 (1.26 g, 90%) as a pale yellow oil: Rf (50% EtOAc/hexanes): 0.80.

Provenance & Evidence