CuI-Catalyzed Cyclization Of Enaminones For The Synthesis Of N-fused Indoles And 2,3-Fused Pyrroles

Nitrogen-containing heterocyclic compounds,such as indoles,pyrroles,and carbazoles,are widely found in many natural products and pharmaceuticals.They also serve as the key skeletons of many complex molecules.This thesis describes the development of new copper-catalyzed methods for the synthesis of heterocyclic compounds such as N-fused polycyclic indoles,2,3-disubstituted indoles,and2,3-fused ring pyrroles.A general introduction of the nitrogen heterocyclic compounds and enaminones are described in Chapter I,including the synthesis of enaminones.Several reactions involving enaminones,such as reactions with different elctrophiles or nucleophilics,pericyclic reactions,dipolar cycloaddition reactions and redox reactions are elaborated in this thesis.The role of enaminones in the synthesis of different types of heterocyclics,for example,pyridines,pyrroles,benzofurans,phenols,quinolones etc are also highlighted.In order to further expand the application of enaminones in the synthesis of nitrogen heterocyclic compounds,we took different types of enaminones such as N-2-iodoaryl enaminones and butnyl phenylamino enaminones as research objects and synthesized different kinds of azacyclic compounds in presence of copper(I)catalyst.Our main research findings in this regard are as followed:Chapter ? describes a copper-catalyzed arylation/acyl migration cascade reaction of enaminones,which allow us to access N-fused polycyclic and 2,3-disubstituted indoles.The robustness of this reaction was demonstrated by 39 examples with as low as 1 mol% catalyst loading.This approach represents good chemoselectivity and functional compatibility for direct access to a wide range of fused polycyclic indoles and 2,3-disubstituted indoles,prevailed motifs found in numerous biologically active molecules.Further transformations of the resulting products provide access to structurally diverse and highly functionalized indoles(i.e.Goniomitine,FK 1052).Chapter ? describes a copper-catalyzed cyclization of enaminones for the synthesis of 2,3-fused pyrroles.This transformation was conducted via 5-exo-dig strategy and no ligand was required in this reaction.Various N-substituted pyrroles e.g.with aryl,alkyl,benzyl,allyl,and methyl heteroaryl groups are found compatible with this method.The 2,3-fused cyclic pyrrole compounds can also be conveniently converted into various forms of fused cyclic pyrrole compounds through transformation of various functional groups under certain conditions...