Design Of C₁-symmetric Chiral Amine Ligands And Their Applications In The Asymmetric Henry Reaction

In this thesis, the preparation of two types of C1-symmetric ligands and theirapplications in the Cu-catalyzed asymmetric Henry reaction were reported. The mainworks that we have done were shown in the following list:1. A new series of bipyridine ligands coupled with Cinchona alkaloids wereprepared in relatively high yield in only one step starting from commercial or readilyavailable materials, and have been developed as chiral ligands for thecopper(II)-catalyzed asymmetric Henry reaction. The catalytic system works wellwith a wide range of aromatic, aliphatic and heteroaromatic aldehydes to afford thecorresponding nitroalkanols with high enantioselectivity (up to92%ee) in good yields(up to89%). A transition state mode was proposed based on1H NMR spectra, X-raystructure, and computational calculations.2. Two chiral C1-symmetric primary-secondary amine ligands were convenientlysynthesized in high yields by only two step starting from commercial or readilyavailable materials, and have been developed as chiral ligands for thecopper(I)-catalyzed asymmetric Henry reaction. This versatile reaction affordedvarious β-nitroalcohols in excellent yields (up to87%)and moderate to goodenantioselectivities (up to88%ee) under the optimized reaction conditions. The chiralinduction mechanism was explained on the basis of a previously proposed transitionstate model.