Catalytic Amine Carbonylation And Suzuki Carbonylation In Polyethylene Glycol Medium

?-ketoamides,N,N'-diarylureas and diarylmethanone are three significant varieties of organic materials,and occur in natural products,drugs and important fragments of biologically active compounds,which have caused the extensive interest in organic synthetic chemistry.Therefore,intense efforts have been focused on the development of ligand-free,eco-friendly,efficient carbonylations of amines to a-ketoamides and N,N'-disubstituted ureas.And a facile,environmentally benign and general iron-catalyzed carbonylative Suzuki reactions using chloroform as carbon monoxide precursor has been developed.Our works mainly includes three parts:(1)the development of ligand-free Pd-catalyzed double carbonylation of arly iodides with amines to a-ketoamides under atmospheric pressure of carbon monoxide and at room temperature.(2)the development of ligand-free and efficient Pd-catalyzed oxidative carbonylation of amines to N,N'-disubstituted ureas under atmospheric pressure of CO.(3)the development of Chloroform as a Carbon Monoxide Precursor for iron catalyzed carbonylative Suzuki reactions.Our primary research results are summarized as follows:1.A ligand-free Pd-catalyzed double carbonylation of aryl iodides with amines to a-ketoamides under atmospheric pressure of carbon monoxide and at room temperature has been demonstrated.We began our studies by investigating the reaction between 1-chloro-4-iodobenzene and cyclohexylamine to optimize reaction parameters,such as catalyst,base,and solvent.We obtained the optimum result when employing Pd(OAc)2 as a catalyst and Na2CO3 as a base in PEG-400 at room temperature under atmospheric pressure of CO gas.With the optimized conditions in hand,a series of aryl iodides and various amine were explored to a-ketoamides,the resulted in over 80%yields.We also made some exploration about the usefulness and the mechanism of this transformation.2.A ligand-free and efficient Pd-catalyzed oxidative carbonylation of amines to N,N'-disubstituted ureas under atmospheric pressure of CO has been developed.We commenced our studies by exploring the reaction of aniline to screen iodine salts,bases,solvent and oxidant.We obtained the optimum result when utilizing Pd(OAc)2 as a catalyst and DABCO as a base and Nal as the promoter in PEG-400 under atmospheric pressure of CO gas.With the facile and practical protocol in hand,we explored the scope of amine under the optimized conditions and the desired products were obtained in more than 80%yields.3.Chloroform as a carbon monoxide precursor for iron-catalyzed carbonylative Suzuki reactions has been invented.Under the model reaction of 1-chloro-4-iodobenzene and potassium phenyl trifluoroborate,we optimized acid,base,solvent,and catalyst.the optimum result was obtained by using PEG-400 as the solvent,FeCl2 as the catalyst,Chloroform as the Carbon Monoxide Precursor,CsOH·H2O and Na2CO3 as the bases,PivOH as the acid and Nal as the promoter at 120?.Under the optimized condition,various aryl iodides as coupling partners to react with different arylboronic acid and potassium aryl trifluoroborates to give diarylmethanone were investigated.Most of the yield of the desired products are in the range from 75%to 94%.We studied competitive reactions between aryl iodides containing electron-withdrawing groups and electron-donating groups,and arylboric acid bearing electron-withdrawing groups and electron-donating groups under the normal conditions.We also studied reaction time profile and isotope 13C labeled chloroform as the carbon monoxide precursor.A preliminary study of the reaction mechanism was conducted,which indicated a free radical process.