Hydrochloric Acid → 1-[2-(3,8-Diazaspiro[5.5]undecan-3-yl)-2-oxo-ethyl]-3-isobutyl-urea

Participants

Reaction Steps

To a solution of tert-butyl 9-[2-(isobutylcarbamoylamino)acetyl]-4,9-diazaspiro[5.5]undecane-4-carboxylate (0.38 g, 0.93 mmol) in 1,4-dioxane (1.75 mL), add 4M HCl in 1,4-dioxane (8.77 mmol). Stir the reaction at room temperature for 5 hours, then concentrate under reduced pressure. Purify the residue by dissolving in methanol and loading into a SCX (ion exchange) column. Rinse the loaded column with methanol (3×25 mL) then flush the column with 2N ammonia in methanol. Combine and concentrate the ammonia washes to yield the final title compound, 1-[2-(4,9-diazaspiro[5.5]undecan-9-yl)-2-oxo-ethyl]-3-isobutyl-urea (0.25 g, 0.81 mmol): MS (m/z): 311.0 (M+H).

Provenance & Evidence