Study On The Cyclization Reaction And Horner-Wadsworth-Emmons Reaction Catalyzed By Lanthanide Silylamides

The cyclization reaction and Horner-Wadsworth-Emmons reaction catalyzed by lanthanide silylamides[(Me3Si)2N]3Ln(?-Cl)Li(THF)3 were studied in this thesis,which is composed of two parts as follows:1.Synthesis of spiro[furan-2,3'-indolin]catalyzed by Lanthanide silylamides[(Me3Si)2N]3Ln(?-Cl)Li(THF)3The reaction of isatins,diethyl phosphite and 2-benzylidene-1,3-diphenylpropane-1,3-diones can be efficiently catalyzed by lanthanide silylamides[(Me3Si)2N]3Ln(?-Cl)Li(THF)3 affording a series of spiro[furan-2,3'-indolin]compounds in high yields.A three-step mechanism involving the Brook rearrangement,Michael addition and intramolecular nucleophilic substitution is proposed.2.Horner-Wadsworth-Emmons reaction catalyzed by Lanthanide silylamides[(Me3Si)2N]3Ln(?-Cl)Li(THF)3Lanthanide silylamides[(Me3Si)2N]3Ln(u-Cl)Li(THF)3 served as efficient catalysts for the Horner-Wadsworth-Emmons reaction of a-dicarbonyl compounds including a-ketoesters and isatins with phosphonates including diethyl(cyanomethyl)phosphonate,ethyl 2-(diethoxyphosphoryl)acetate and diethyl(tosylmethyl)phosphonate to produce alkenes in moderate to excellent yields.This is the first report of catalyzed Horner-Wadsworth-Emmons reaction.