Acetophenone → N-(1-Phenylethyl)cyclopropanamine

To a solution of 1-phenylethanone (1 eq.) in dichloromethane (0.17 M) was added cyclopropylamine (3 eq.) and magnesium sulfate (9 eq.). The resulting mixture was stirred at reflux for 2 days. The insolubles were then filtered off and the filtrate evaporated in vacuo. The resulting residue was taken up in methanol (0.2 M) and added sodium borohydride (1.5 eq.). The reaction mixture was then stirred at RT overnight. After quenching with 1 N aq. HCl, the volatiles were removed in vacuo. The resulting residue was partitioned between 1 N NaOH and extracted with ether. The combined organic extracts were washed with brine, dried over MgSO4 and filtered. Concentration of the filtrate in vacuo afforded the title compound as a colorless oil.