Development of Chiral Ligand Based on Double Asymmetric Induction and Application to Catalytic Reaction.

点击翻译按钮获取中文摘要

The envisioned ligand is monodentate phosphine ligand for palladium catalyst. The new chiral ligand was designed based on the double asymmetric induction methodology which is well known in a usual asymmetric reaction. Thus, the combination of axial chirality and chiral auxiliary constitutes the backbone of the chiral ligand. Initially, the axially chiral fragment was binaphthalene framework, because the skeleton has been proved to exhibit most efficient induction ability. As an another chiral auxiliary, oxazohdine and acetal structures were selected. Diphenylphosphino group and chiral auxiliary were planned to be put on 2 and 2' positions on the binaphthalene framework. Although the most desired ligand could not be synthesized in spite of intensive trials, another ligand was prepared and tested in several palladium catalyzed reactions. Unfortunately, the high asymmetric induction was not observed so far under the typical reaction conditions in each catalyzed reaction. However, this concept is believed to be anew direction to obtain more efficient chiral ligand.