Construction Of N-Heterocyclic Compounds And (E)-α-Alkynyl-α,β-Unsaturated Esters Catalyzed By Copper Immobilized On Mesoporous MCM-41

This dissertation mainly describes the applications of mesoporous material MCM-41-immobilized copper complexes in the construction of N-heterocyclic compounds and（E）-α-alkynyl-α,β-unsaturated esters,the research works are divided four parts as follows:1.The condensation of mesoporous material MCM-41 with（4-chloromethyl）-phenyltrichlorosilane in toluene generated a chloromethyl-functionalized mesoporous material[MCM-41-CH₂Cl],the latter was then reacted with N-Boc-4-hydroxyl-L-praline,followed by deprotection to provide the L-Proline-functionalized mesoporous material[MCM-41-L-Proline].The supported copper catalyst[MCM-41-L-Proline-Cu（OTf）₂]was obtained by the reaction of MCM-41-Proline with Cu（OTf）₂ in acetone under reflux and was characterized by different physical and chemical techniques.We investigated the catalytic properties of MCM-41-L-Proline-Cu（OTf）₂in the cyclization reaction of 2-benzoylpyridines andα-amino acid.The results indicated that this heterogeneous copper complex exhibited high catalytic activity and could be recycled up to eight times with almost consistent activity.Thus,the present work provides a highly efficient and practical route for the synthesis of a variety of imidazo[1,5-a]pyridine derivatives.2.The supported copper catalyst[MCM-41-L-Proline-CuCl]was prepared by the reaction of MCM-41-Proline with CuCl in acetone under reflux and its structure was characterized.We investigated the catalytic performance of MCM-41-L-Proline-CuCl in the three-component tandem reaction of terminal alkynes,organic azides and alkynyl bromides.The results indicated that MCM-41-L-Proline-CuCl exhibited excellent catalytic activity and could be reused at least seven times without significant loss of activity,thereby providing a novel and green method for the one-pot synthesis of 5-alkynyl-1,2,3-triazole derivatives.3.The condensation reaction of MCM-41 with 3-（2-aminoethylamino）propyl-trimethoxysilane in toluene followed by the silylation with Me₃SiCl afforded the3-（2-aminoethylamino）propyl-functionalized mesoporous material[MCM-41-2N].Then MCM-41-2N was reacted with Cu（OTf）₂ or CuCl in DMF to give supported copper catalysts MCM-41-2N-Cu（OTf）₂ or MCM-41-2N-CuCl,respectively.We investigated the three-component coupling reaction of 2-aminopyridines,aldehydes and terminal alkynes by using MCM-41-2N-Cu（OTf）₂ and MCM-41-2N-CuCl as a binary catalytic system.The results indicated that this heterogeneous binary catalytic system showed high catalytic activity and could be recycled up to eight times with almost consistent activity.The present work provides a novel,highly efficient and practical route to a variety of imidazo[1,2-a]pyridine derivatives.4.The supported copper catalyst[MCM-41-2N-CuI]was obtained by the reaction of MCM-41-2N and CuI in DMF at room temperature.We studied the catalytic behavior of MCM-41-2N-CuI in the three-component cascade reaction of terminal alkynes,diazo esters and aldehydes.It was found that the heterogenous copper（I）-catalyzed three-component cascade reaction proceeded smoothly under mild conditions to afford a variety of（E）-α-alkynyl-α,β-unsaturated esters in good to excellent yields.The heterogeneous copper catalyst could be recycled up to eight times whilst maintaining a high catalytic activity.