Acetic Anhydride → 7-Acetyl-2,7-diaza-spiro[4.5]decane-2-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of 2,7-diaza-spiro[4.5]decane-2-carboxylic acid tert-butyl ester (140 mg, 0.58 mmol) in DCM (5.8 mL) was added acetic anhydride (82 μL, 0.87 mmol) and triethylamine (244 μL, 1.75 mmol) and the reaction mixture was stirred (rt, 16 h). The reaction mixture was diluted with DCM (6 mL), washed with water (3×4 mL) and brine (1×4 mL). The organic layer was dried, filtered and concentrated in vacuo to provide 7-acetyl-2,7-diaza-spiro[4.5]decane-2-carboxylic acid tert-butyl ester as a brown oil (164 mg, 100%). This intermediate was dissolved in DCM (0.75 mL), treated with HCl (4M in dioxane, 0.75 mL) and stirred (rt, 16 h). The dispersion was concentrated in vacuo to yield then desired product (128 mg, 100%). MS (ESI): mass calcd. for C10H18N2O, 182.14; m/z found, 183.1 [M+H]+.

Provenance & Evidence