The Research On Cyclopropanation And [3+2+2] Cycloaddition Reaction Of Metal Carbene

Selectivity control of metal carbene reaction is key point and difficulty in this field.This thesis mainly focuses on two types of catalytic cyclization reaction of metal carbene,which can efficiently produce cyclic compound with structural diversity.And high selectivity control,incluing enantioselectivity is realized in these transforamtions with compatible catalysts or catalytic system.1.Highly enantioselective synthesis of spirocyclopropyloxindoles via Rh(II)-catalyzed asymmetric cyclopropanation reaction.A chiral dirhodium(II)carboxylate complex catalyzed enantioselective cyclopropanation reaction of N-Boc diazooxindoles with olefins,including aryl,alkyl,cyclic,and disubstituted olefins,under mild conditions is described.This reaction provides complementary access to the corresponding chiral spirocyclopropyloxindole products in good to high yields with good to excellent enantioselectivities.2.Gold-catalyzed tandem dual heterocyclization of enynones with 1,3,5-Triazines:bicyclic furan synthesis and mechanistic studiesA general and unprecedented gold-catalyzed tandem dual heterocyclization reaction of enynones with 1,3,5-triazines has been developed,which provides bicyclic fused furans in high to excellent yields under mild reaction conditions.In addition,mechanistic studies indicate that the reaction goes through a stepwise [3+2+2]-cycloaddition of furanyl gold intermediate,which is generated from gold-catalyzed cyclization of enynone,with two molecules of formaldimines derived in situ from 1,3,5-triazine,instead of a formal[4+3]-cycloaddition.