Design And Synthesis Of The Novel C₂ Axial Chiral Dithiourea Catalyst And Its Application In Asymmetric Tandem Reaction

Chiral amide organic catalysts are widely used in many natural science and technology fields such as food processing,medicine,agriculture,biology and materials,so the design and synthesis based on amide catalysts have important application value.Chiral amide catalysts have the ability to activate substrates by hydrogen bonding,which can effectively promote the occurrence of asymmetric reactions.At present,a variety of chiral amide catalysts have been developed and synthesized,such as: chiral amide catalyst prepared with cyclohexanediamine as the backbone,cinchona alkaloid type chiral amide catalyst,1,2-diphenylethyl ether Chiral amide catalysts,prolineamide catalysts,etc.prepared from diamine as skeleton.In this paper,a series of highly active,highly selective and structurally tunable up and down symmetry organic small molecule catalysts for multiple hydrogen bond amides have been designed and synthesized.Using 2-naphthol-3-carboxylic acid as raw material,through multi-step chemical modification,an amide organic catalyst containing a chiral BINOL skeleton was synthesized and applied to asymmetric intramolecular 1,3-dipolar cycloaddition Tandem reactions and asymmetric reactions of diketenes with indole oxides.More than a dozen benzopyran compounds and a dozen spiro-epoxy indole compounds were synthesized,all of which were obtained in good yields and selectivity to alcohol.The effects of catalyst,catalyst dosage,solvent,temperature and other factors on the reaction were also investigated.The obtained products were characterized by NMR,MS,etc.