Development of Highly Efficient Asymmetric Reactions Based on Construction of Functionalized Multinucleating Chiral Reaction Field

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The development of a practical and efficient method for the construction of chiral molecules is essential to explore new medicines and agricultural chemicals. In order to develop more efficient chiral environment, incorporation of multi metal centers should be more effective, because the cooperative action of the metals can efficiently control the stereochemical course of the reactants to produce the corresponding optically active chemicals.A catalytic asymmetric 1,3-dipolar cycloaddition reaction of a nitrone possessing diisopropyl amide moiety to g-substituted allylic alcohols was achieved by using diisopropyl (R,R)-tartrate as a chiral auxiliary to afford the corresponding 3,4,5-trisubstituted isoxazolidines with excellent enantioselectivity up to over 99% ee.The asymmetric 1,3-dipolar cycloaddition of nitrile oxides, generated in situ from aldoximes by direct oxidation with t-butyl hypochlorite, to 2-propen-1-01 was achieved by utilizing diisopropyl (R,R)-tartrate as a chiral auxiliary to afford the corresponding R-2-isoxazolines with high enantioselectivity up to 96% ee.γ-Lactams can be synthesized from the reaction of N-tosyl homoallylamines catalyzed by palladium and copper salts under normal pressure of CO and O2 at rt. Monocarbonylation proceeded by the use of [PdCl_2(CH_3CN)_2] and CuCl to afford 3-methyl-2-pyrrolidinones, while the use of PdCl_2 and CuCl_2] chaneged the reaction course to the dicarbonylation to produce 3-(alkoxycarbonyl)methyl-2-pyrrolidinones in good yield, respectively. In the presence of chiral bioxazoline ligand, the optically active γ-lactams could be obtained.