Organocatalytic Asymmetric Phosphination And [4+2] Cycloaddition Reaction Catalyzed By C₂-symmetric Bis（oxazolines）/Ni（Ⅱ） Complexes

Optically active α-amino phosphonic acid derivatives are an important class of molecular skeletons presenting in many natural and bioactive compounds, and also play an important role in industrial, agricultural and pharmaceutical chemistry. Organocatalytic asymmetric carbon-phosphorus bond-forming processes has attracted considerable attention over the last few years. Herein, we synthesized some chiral catalysts and bisoxazolines ligands for asymmetric catalysis and organic synthesis. Among them, successfully implemented enantioselective phosphination and hydrophosphonylation reactions between azomethine imines and diaryl phosphine oxides and dialkyl phosphites are respectively developed by the use of a chiral squaramide as the hydrogen bonding organocatalyst.Asymmetric catalysis has become an significant means of the preparation of optical active substances. Organocatalysts are easily avaliable and show good catalytic efficiency, bisoxazoline ligands in a variety of asymmetric reactions exhibit excellent catalytic activity. Thus, we synthesized some organocatalysts such as squaramide derived from quinine and bisoxazolines ligands derived from pyridine and(1S,2R)-(+)-2-Amino-1,2-diphenylethanol. In addition, we also synthesized some chiral N-Heterocyclic Bis-Carbene Complexes from binaphthol.This thesis mainly report enantioselective phosphination and hydrophosphonylation reactions between azomethine imines and diaryl phosphine oxides and dialkyl phosphites catalyzed by chiral squaramide. A series of screening optimization condition, which afforded two type of α-amino phosphorus derivatives containing products in high yields(up to 99% yield) with good to excellent enantioselectivities(up to >99% ee).Then we explored asymmetric [4+2] cycloaddition reaction of β, γ-unsaturated α-keto esters with oxazolones catalyzed by C2-symmetric Bis(oxazolines)-metal complexes. In this reaction, we can obtain highly functionalized δ-lactone with adjacent α-quaternary-β-tertiary stereocenters in general yields and with good enantioselectivities(up to 80% ee).