Ring opening of cyclohexene oxide (I) with aqueous methylamine gave trans 2-(methylamino)cyclohexanol (II), which was further cyclized to the aziridine (III) upon treatment with chlorosulfonic acid and then with NaOH. Subsequent condensation of (III) with pyrrolidine (IV) yielded the racemic trans diamine (V). Resolution was achieved by fractional crystallization of the 2,3-di-p-toluoyl-D-tartaric acid salt in MeOH. The required (-)-(R,R) enantiomer was finally coupled with 4-benzothiopheneacetyl chloride (VI) to provide the corresponding amide.