Three manganese(II) complexes, namely [Mn(1)(ClO4)(2)] (3), [Mn(1)(acac)(2)] (4), and [Mn-2(1)(acac)4] (5), were isolated from solutions of Mn(ClO4)(2) or Mn(acac)(2), and an easily accessible diimine ligand (1S,2S)-N,N'-bis-pyridin-2-ylmethylene-cyclohexane-1,2-diamine (1). Their structure was determined by X-ray crystallography, and these complexes proved to be catalysts for asymmetric sulfide oxidation by H2O2. Enantiomeric excesses ranging from 5% to 62% were obtained with a variety of aryl alkyl sulfides. We also observed an interesting "chirality switch" effect by the achiral acac anion reversing the enantioselectivity of the complex [Mn(1)(ClO4)(2)] from the S to the R sulfoxide enantiomer.