The reaction of enantiomerically pure 2-substituted 1-phenylethyl-aziridine with methyl trifluoromethanesulfonate generated a stable methylaziridinium ion, which was reacted with various external nucleophiles, including nitrile, to yield synthetically valuable and optically pure acyclic amine derivatives in a completely regio- and stereoselective manner.

The ring opening of 2-substituted N,N-dibenzylaziridinium ions by bromide exclusively occurs at the substituted aziridine carbon atom in a stereospecific way, whereas the opposite regioselectivity was observed for hydride-induced ring opening at the unsubstituted position; furthermore, this unprecedented hydride-promoted reactivity was validated by means of Density Functional Theory (DFT) calculations.

Substituted imidazolidin-2-ones deduced as potential inhibitors of IleRS by docking simulations were synthesized from an aziridine-2-carboxaldehyde. Reductive amination of an aziridine-2-carboxaldehyde with dipeptides for the substituents at N1 and followed by aziridine-ring expansion with triphosgene afforded 4-chloromethylimidazolidin-2-ones whose chloride were further manipulated towards phenylurea, pyrimidin-2-yl-urea or benzenesulfonamide at C4.

Ring opening reactions O 0132The Preparation of Stable Aziridinium Ions and Their Ring Openings. -The ring opening by nucleophiles proceeds in a completely regio-and stereoselective manner depending on the substituent at C2 of the aziridine. Thus, the procedure offers an efficient and enantioselective route to acyclic N-methyl amines. -(KIM, Y.; HA*, H.-J.; YUN, S. Y.; LEE, W. K.; Chem.

Amino alcohols Q 0240Nucleophile-Dependent Regioselective Ring-Opening of 2-Substituted N,N-Dibenzylaziridinium Ions: Bromide versus Hydride. -Ring opening of aziridinium ions, generated in situ from substrates (I), in the presence of bromide occurs exclusively at the substituted aziridine carbon. The opposite regioselectivity is observed in the presence of hydride which affords the protected amino alcohols (IV). -(YUN, S. Y.; CATAK, S.; LEE, W. K.; D'HOOGHE, M.; DE KIMPE, N.; VAN SPEYBROECK, V.; WAROQUIER, M.; KIM, Y.; HA*, H.-J.; Chem.