A new approach towards 1-phenyl and 1-benzyl substituted 2-(aminomethyl)cyclopropanecarboxamides as novel derivatives of the antidepressant Milnacipran.

2-(2-Cyano-2-phenylethyl)aziridines were converted into novel trans-2-aminomethyl-1-phenylcyclopropanecarboxamides via regiospecific ring opening and 3-exo-tet cyclisation, thus providing the first convenient entry into the trans-isomer of Milnacipran as a useful template for further derivatisation. Furthermore, unprecedented 2-aminomethyl-1-benzylcyclopropanecarboxamides have been synthesized using two different routes starting from 2-(2-cyanoethyl)aziridines, both involving alpha-benzylation with respect to the nitrile group and aziridine to cyclopropane ring transformation.