Study On Rhodium-Catalyzed Oxidative Carbonylation Of Amine Compounds

Carbamates and o-aminoaryl carboxylates are not only two important organic intermediates in organic chemistry and material chemistry,but also widely found as structural fragments in biologically active natural products and numerous alkaloids.Therefore,the synthesis of these two types of compounds has attracted the attention of many researchers.Using CO as a carbonyl source through transition metal catalysis can efficiently,conveniently,and greenly synthesize these two types of compounds.Based on this,this thesis aims to explore and establish new catalytic systems for the efficient preparation of carbamates and o-aminoaryl carboxylates via rhodium-catalyzed oxidative carbonylation of amine compounds.The specific research content is as follows:Rhodium catalyzed oxidative carbonylation of primary amines to carbamates1.Using Rh Cl₃·3H₂O as a catalyst and CO as a carbonyl source,aromatic and aliphatic primary amine substrates can undergo oxidative carbonylation reactions with primary,secondary,and tertiary alcohols in a mixed solvent of DMF and toluene,providing carbamate compounds in medium to excellent yields.This method solves the problems of low yields of secondary alcohol-and tertiary alcohol-involved similar carbonylation reactions in previous studies,and provides a new method for the synthesis of carbamates.2.Rhodium catalyzed ortho C（sp²）-H carbonylation and esterification of N-aryl secondary aminesUsing Rh Cl₃·3H₂O as a catalyst and CO as a carbonyl source,the reaction was carried out in a mixed solvent of DMF and anisole.The ortho C（sp²）-H carbonylation esterification of various N-aryl secondary amines,including tetrahydroquinoline,was achieved.This method can currently complete the ortho C（sp²）-H carbonylation esterification of heterocyclic compounds such as N-alkylanilines and tetrahydroquinolines with moderate to good yields,but the types of substrates investigated are still limited.In the subsequent study,N-aryl secondary amine substrates that can be adapted to this system will be further optimized and expanded.