Modulating the Reactivity of Heterocyclic Ketene Aminals in MCR: Selective Construction of Tetrahydrobenzo[b]imidazo[3,2,1-ij][1,8]naphthyridines
摘要:
Two new kinds of tetrahydrobenzo[b]imidazo[3,2,1-iota j][1,8]naphthyndine derivatives have been successfully synthesized by cascade reactions including Knoevenagel condensation, aza-ene reaction, imine-enamine tautomenzation, cyclocondensation, and intramolecular SNAr of precursors 2-(2-chloroaroyl)methyleneimidazolidines with aromatic aldehydes and ethyl acetoacetate or Meldrum's acid under mild conditions, respectively These studies highlighted the concept of a substrate-design approach to the development of novel multicomponent reactions by simply incorporating an o-halo group into the aryl ring of 2-benzoyl-methyleneimidazolidine as new synthons In this domino reaction, at least six different active sites are involved, two C-C bonds, two C-N bonds, and two new rings are constructed with all reactants efficiently utilized in the chemical transformation
Modulating the Reactivity of Heterocyclic Ketene Aminals in MCR: Selective Construction of Tetrahydrobenzo[b]imidazo[3,2,1-ij][1,8]naphthyridines
摘要:
Two new kinds of tetrahydrobenzo[b]imidazo[3,2,1-iota j][1,8]naphthyndine derivatives have been successfully synthesized by cascade reactions including Knoevenagel condensation, aza-ene reaction, imine-enamine tautomenzation, cyclocondensation, and intramolecular SNAr of precursors 2-(2-chloroaroyl)methyleneimidazolidines with aromatic aldehydes and ethyl acetoacetate or Meldrum's acid under mild conditions, respectively These studies highlighted the concept of a substrate-design approach to the development of novel multicomponent reactions by simply incorporating an o-halo group into the aryl ring of 2-benzoyl-methyleneimidazolidine as new synthons In this domino reaction, at least six different active sites are involved, two C-C bonds, two C-N bonds, and two new rings are constructed with all reactants efficiently utilized in the chemical transformation