Abstract: The para-substituted (E)-stilbenes 2a-2e were prepared respectively by Wittig reaction and nucleophilic substitution in 59%～80% yields. The asymmetric dihydroxylation was carried out by the modified Sharpless method. The amount of OsO₄was increased to 1%(mole ratio) and the amount of ligand to 5%(mole ratio). All asymmetric dihydroxylation was performed at 0 ℃, affording the corresponding chiral 1,2-diol in 77%～87% yield with 82%～93% e.e..

Key words: para-Substituted (E)-stilbene, Asymmertric dihydroxylation, Chiral1,2-diol