Catalyst-Free Or Copper (?)-Catalyzed Synthesis Of Fused Heterocycles Containing Nitrogen

Because the organic compounds containing nitrogen-atom are widely distributed in nature,how to construct these heterocyclic compounds is one of important contents in organic chemistry.Six series of fused heterocyclic compounds were built through finding environmentally-friendly catalyst system.In recent years,Copper-catalyzed Ullmann reaction is an important method for the formation of C-C,C-N,C-O,and C-S bonds,much attention has been devoted to this known name reaction,it has been made to a great progress.The first chapter in this article introduces the research situation on quinoline derivatives containing nitrogen-atom and also briefly describes copper-catalyzed Ullmann reaction in recent years.The second chapter introduces that three series of fused heterocyclic compounds were synthesized in high regioselectivity via a three-component one-pot reaction of1H-benzo[d][1,2,3]triazol-5-amine,aromatic aldehydes,1,3-dicarbonyl compounds under catalyst-free conditions.The 1,3-dicarbonyl compounds included 5,5-dimethyl-1,3-cyclohexanedione,2,4-piperidone-1-carboxylate,and tetronic acid.Tetrahydro-1H-[1,2,3]triazolo[4,5-a]acridine-10-?6H?-one,tetrahydro-1H-[1,2,3]triazolo[4',5':3,4]benzo[1,2-b][1,6]naphthyridine-9-?6H?-carboxylate,1H-furo[3,4-b][1,2,3]triazolo[4,5-f]quinoline-9-?6H?-one derivatives were synthesized in high yields,respectively.The products were characterized according to ¹H NMR,¹³C NMR,IR and HRMS.A reasonable reaction mechanism was proposed according to the final structure of the products.In the third chapter,an intramolecular C-N coupling reaction was successfully achieved by Ullmann reaction under relatively mild conditions using copper???as an efficient catalyst.The fused heterocyclic compounds with six rings were obtained via a three-component reaction of 1H-benzo[d][1,2,3]triazol-5-amine,o-bromobenz aldehyde,1,3-carbonyl compounds?1,3-cyclohexanedione,piperidine-2,4-dione?,using CuI as a catalyst,L-proline as a ligand,Cs₂CO₃ as a base,and 1,4-dioxane as a solvent.The fused hexacyclic heterocycles included dihydroquinolino[4,3,2-mn][1,2,3]triazolo[4,5,1-de]acridin-14?11H?-one,and naphthyridino[4,3,2-mn][1,2,3]triazolo[4,5,1-de]acridine-13?14H?-carboxylate.All the products were determined by ¹H NMR,¹³C NMR,HRMS and IR,and a possible reaction mechanism containing an intramolecular C-N coupling reaction was put forward.In the final chapter,intermolecular S_N-AR reaction was successfully achieved involving an Ullmann-type reaction catalyzed by CuI/L-proline in the presence of C_S2CO_3.The reaction between 1,3-cyclohexanedione and 2-?2-bromophenyl?-1H-benzo[d]imidazole derivatives was carried out to synthesize 2,3-dihydro-benzo[4,5] imidazo [1,2-f] phenanthridine-4?1H?-one derivatives in high yields.It is a subsequent inter-molecular S_N-AR reaction,intra-molecular cyclization and dehydration which is put forward to explain the formation of the final products.All compounds are characterized by proton nuclear magnetic resonance spectroscopy,high-resolution and infrared.Some of the compounds have also been characterized by ¹³C NMR spectra.Compound 4a was further confirmed by single crystal X-ray diffraction analysis.