Studies Of Cyclization Reaction Of Alkene Or N-Allenyl Amides Synthesis Of Heterocyclic Compounds

Indolizine and Azetidine derivatives are two important kinds of nitrogen-containing heterocyclic compounds,which has been a focused research topic in organic chemistry.In this dissertation,we designed reasonable substrate,we have developed a copper-catalyzed oxidative cross-coupling/cyclization reaction between alkenes and 2-(pyridin-2-yl)acetate to build indolizine derivatives,and a nickel-catalyzed enantioselective[2+2]cycloaddition of N-sulfonyl ketimioester and N-allenyl amides to build Azetidine derivatives.A copper-catalyzed oxidative cross-coupling/cyclization reaction between alkenes and 2-(pyridin-2-yl)acetate to build indolizine derivatives was studied.We found optimum reaction conditions by scanning of different copper catalyst,temperature,solvents,and additives.With Cu(OAc)₂·H₂O(3.0 eq.)/I₂(1.0 eq.)as catalyst,NBu₄Cl(1.0 eq.)as additive,the reaction proceeds efficiently in DCE at 100 ? after 24 h,we get the desired products ranges from 15%to 90%yield,which could tolerate a lot of functional groups,terminal olefins and nonterminal olefins could react,2,3-di-and 1,2,3-trisubstituted indolizines could be easily synthesized.The mechanism of the experiment is discussed in this dissertation,control experiment showed that product was not observed when a radical scavenger 2,2,6,6-tetramethylpiperidin-1-yloxyl(TEMPO)was added to the reaction system,which indicated that the reaction might undergo a radical pathway.A nickel-catalyzed enantioselective[2+2]cycloaddition of N-sulfonyl ketimioester and N-allenyl amides to build Azetidine derivatives was studied.We found optimum reaction conditions by scanning of chiral ligand,catalyst,solvents,temperature and additives.With 12 mol%chiral bisoxazoline ligand L3-1,10 mol%Ni(Cl O₄)₂?6H₂O as catalyst and 4?molecular sieve as additive,the reaction proceeds efficiently in DCE at 25? to give the desired products ranges from 52%to 90%yield and up to 99%enantioselectivity,which could tolerate a lot of functional groups.A series of the substrate can react smoothly,and obtain excellent results.