The Study Of Chiral Amino Alcohols-Cu(?) Complex Catalyzed Asymmetric Henry Reaction And The Application

The catalytic asymmetric Henry reaction has been a hot research topic since its first report in 1990s.Besides as a classical carbon-carbon bond-formation method,catalytic asymmetric Henry reaction can enantioselectively accomplish the Carbon chain growth.And the Henry product,chiral P-nitro alcohols,can be conveniently converted into many functional groups via simple transformation.Therefore,it give us an easy and efficient method to synthesize many chiral molecules and blocks,which play an important role in development of chiral natural products and drugs.Many catalytic systems have been developed in the last few decades,however,most of them share some disadvantages such as expensive catalysts with high loadings,harsh reaction conditions,and poor generality of substrate.Chiral amino alcohols are widely applied in asymmetric catalysis because of their advantages such as abundant sources,easy preparation,excellent coordination ability and versatile coordination modes with transition metals.Previously our lab have developed new chiral amino alcohol-copper(II)complexes as efficient catalyst for asymmetric Henry reaction.The purpose of this dissertation is to further exploit the application of our chiral amino alcohol-copper(II)catalytic system in Henry reaction,as well as their further utilization in the efficient synthesis of chiral natural products and drugs.This dissertation mainly includes the following two parts:1.Efficient synthesis of chiral benzofuryl ?-amino alcohols via a catalytic asymmetric Henry reactionThe catalytic asymmetric Henry reaction of benzofuran-2-carbaldehydes with nitromethane were carried out in the presence of chiral amino alcohol-copper(II)complex as the catalyst.All the substrates stested herein gave their corresponding Henry adducts(benzofuran-2-nitroethanols)with moderate to good isolated yields with good to excellent ee values.Using this reaction,structurally-diverse benzofuryl?-amino alcohols with impressive physiological and drug activities such as?-adrenergic blocking activities could be conveniently prepared in a one-pot transformation from the Henry adducts.2.Efficient synthesis of(-)-spirbrassinin and analogue via a catalytic asymmetric Henry reactionIn the presence of chiral amino alcohol-copper(II)complex,various isatins reacted well with nitromethane,which gave good isolated yields and medium enantioselectivity.Further transformation of the isatin-nitromethane Henry adducts in short steps afforded a kind of phytoalexins(-)-spirbrassinin and its analogues,which displays various biological properties such as antifungal and antitumor.We wish this work may facilitate the biological activity studies in the near future.