Preparation and characterization of dioxoruthenium(vi) picket-fence complexes bearing optically active alpha-methoxy-alpha(trifluoromethyl)phenylacetyl residues on both sides of the porphyrin plane (alpha,beta,alpha,beta and alpha,alpha,beta,beta isomers) are described oxidation of racemic benzyl(methyl)(phenyl)phosphine by the alpha,beta,alpha,beta isomer leads to the formation of optically active phosphine oxide (enantiomeric excess 41%) and proceeds with retention of the configuration of the phosphorus atom.