Catalytic asymmetric epoxidation with a chiral ruthenium porphyrin and N-oxides

Abstract

The enantiomerically pure ruthenium porphyrin 3 was synthesized in very high yield by refluxing the porphyrin 2 with Ru₃(CO)₁₂ in phenol; its subsequent use in the catalytic asymmetric epoxidation of olefins with 2,6-dichloropyridine N-oxide as terminal oxidant, to afford epoxides in good yields and with enantioselectivities up to 77%, is reported.

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