Research On Construction Of Chiral Quternary Alcohol Compounds By Amino Acid Salt Catalyzed Asymmetric Aldol Reaction

Organocatalyzed asymmetric reactions which take great advantage of cheap starting materials,easy operation and less waste,is one of the most important ways to produce chiral building blocks.However,the disadvantages of organocatalysis such as limited activation model,relative low catalytic ability and high catalyst loading are also revealed in the research process.On the other hand,the amino acid metal salts,which take great advantage of both organocatalyst and Lewis acid catalyst,are much less studied.Thus,we hope to develop novel catalytic asymmetric reactions based on the exploration of the synthetic potential of amino acid metal salts.Chiral tertiary alcohols are the key structures of many natural products and biologically active compounds;besides,the polyhydroxy compound with multiple chiral centers can be employed in the synthesis of ligands and carbohydrates.Thus,developing efficient methods for the catalytic asymmetric synthesis of chiral alcohols is of great importance.In this thesis,we developed an amino acid salt catalyzed direct aldol reaction between hydroxyacetone and ?-keto esters,which afforded the 1,2-diols in high diastereoselectivities and enantioselectivities;we also evaluated the catalytic ability of amino acid salts in controlling both the enantioselecitivity and regioselectivity of the direct aldol reaction between acyclic ketones and isatins,affording the desired products with good yield and optical purity.The above researches provided two novel amino acid salts catalyzed asymmetric transformations for the construction of chiral alcohol compounds,which inspired the further exploration of catalytic ability of amino acid salts in our group.