Catalytic and asymmetric epoxidation by novel D4-symmetric chiral porphyrin derived from C2-symmetric diol

Novel D-4-symmetric chiral porphyrin le was efficiently prepared by utilizing C-2-symmetric diol as the chiral source. Asymmetric epoxidation of styrene and trans-beta-methyl styrene by the 1c-Fe(Br)/PhIO system showed moderate enantioselectivity, and enantiomeric excesses were markedly increased by the introduction of electron-withdrawing groups at the aromatic rings of styrenes. (C) 2004 Elsevier B.V. All rights reserved.