Synthesis of trans-1,2-diamines via sequential opening of cyclohexene oxide and aziridinium ions

Abstract

A synthesis of trans-1,2-diaminocyclohexane derivatives via opening of cyclohexene oxide with secondary amines followed by preparation and opening of the corresponding aziridinium ions in situ by primary and secondary amines is described. Use of chiral α-methylbenzylamine for the opening of aziridinium ions gave a mixure of diastereomers that are readily separated by column chromatography. The C2 symmetric trans-1,2-bis (N-pyrrolidino)cyclohexane was resolved to obtain nonracemic samples that can be readily enriched by co-crystallization with fumaric acid to obtain enantiomerically pure compounds.