关键词: 手性卟啉, 不对称催化, e.e.值, 构象分析

Abstract: Novel mono-faced bridged chiral porphyrins 1a and iron complex 1b were synthesized and characterized. Conformation analysis was performed by using molecular mechanics conformation search method. The theoretic viable lowest energy conformation of compound 1a greatly coincided with ¹H NMR data. Compound 1b was used as the catalyst in asymmetric styrene devivatives epoxidation. In the absence of nitrogen base ligand, the epoxides were formed on a lower e.e.(25%—28%), when axial ligand was present, compound 1b exhibited an increased epoxidation rate, yield and much higher e.e.(73%—80%). The added nitrogen base can efficiently block the oxidation reaction at the unhinded side of the porphyrin ring and directionally control the oxygen transfer and substrate approach to the chiral cavity.

Key words: Chiral porphyrin, Asymmetric catalysis, e.e. value, Conformation analysis