Two new chiral unsymmetrical (non-C-2-symmetric) Schiff-base ligands containing salicylaldehyde and 1-(2-hydroxyphenyl) ketone units were synthesized from (R,R)-1,2-diphenylethylenediamine as the chiral diamine using a stepwise approach. The Mn(III) complexes of the ligands were subsequently used as catalysts in asymmetric epoxidation of unfunctionalized alkenes and the results were compared with those obtained using typical C-2-symmetric Mn(III)-salen complexes. Possible reasons for the differences in reactivity and selectivity between the two types of catalysts are briefly discussed. (C) 2002 Elsevier Science B.V. All rights reserved.