Synthesis Of Chiral N,P-bidentate Ligand From Chiral Amino Acids

The meaning, significance, characteristics and the origin of chirality were briefly concerned. We gave a brief introduction on the classification and characteristics of chiral phosphine ligands, then we reviewed the application of chiral phosphine ligands in asymmetric catalytic synthesis, including asymmetric hydrogenation, asymmetric hydroformylation, asymmetric alkylation and asymmetric cycloaddition. Clear the content of this thesis.This thesis focuses on the design and synthesis of chiral N, P-ligand. We designed and synthesized a series of chiral N, P-ligand derived from the L- Phenylalanine and L-Phenylglycine, which made a favorable bedding for further synthesis of chiral catalysts. Every step of the reaction conditions were optimized to solve the problem of difficult synthesis of chiral ligands and high cost. The main work of this thesis is as follow:First, L-Phenylalaninol and L-Phenylglycinol were prepared by the reduction of KBH4/AlCl3. Then the amino alcohols reacted with different benzaldehyde to give the corresponding Schiff bases. We investigated the effects of microwave power and reaction time on the yield of Schiff bases. Tosylation of the Schiff bases gave the ester tosylate using TsCl in the present of Et3 N. We investigated the effects of TsCl dosage and temperature on the reaction. Schiff bases reacted with SOCl2 to give the chlorides. At last, the substrate reacted with Ph2 PLi gave the chiral N, P-ligand.The details for synthesis of the Amino alcohols, Schiff bases, Sulfonyl compounds, Chlorides and chiral N, P-ligand were described. These compounds were characterized using 1H NMR, 13 C NMR, MS and IR spectrum.