Hydrochloric Acid → N-[(1S,2S,5R)-1-(3-Aza-bicyclo[3.1.0]hex-2-yl)methyl]-2,2,2-trifluoro-acetamide

A solution of HCl in dioxane (4 M, 30 mL) is added to a solution of (1S,2S,5R)-2-[(2,2,2-Trifluoro-acetylamino)-methyl]-3-aza-bicyclo[3.1.0]hexane-3-carboxylic acid tert-butyl ester (31.6 mmol) in dioxane (30 mL) and the mixture is stirred for 60 min at RT and for 30 min at 45° C. The solvents are removed in vacuo and the obtained solid is washed twice with a small volume of dioxane to give the desired product which is used without further purification in the next step.