Synthesis of cyano-2,3-dihydropyrrolo[1,2-f]phenanthridine derivatives via a domino-Knoevenagel-cyclization

Abstract

In a new multicomponent reaction phenanthridine reacts with isocyanides and malonitrile in the presence of benzaldehyde derivatives to produce 2-aryl-3-(alkyl- or arylimino)-2,3-dihydropyrrolo[1,2-f]phenanthridine-1,1(12b H)-dicarbonitrile in a simple, mild, and efficient protocol in excellent yields.

A High Performance Route for the Synthesis of Dihydropyrrolo[1,2‐f]phenanthridine Scaffolds by using a One‐pot Four‐component Reaction

“…It should be mentioned that any proton shift and ‐CN elimination have not been occurring in reaction conditions. A proposed mechanism for the synthesis of compound 5a–f is shown in Scheme , which is in agreement with the predicted structure .…”

“…Because of the pyridine ring nature, synthesis of substituted pyridines by electrophilic aromatic substitution reaction is difficult. Because of the importance of nitrogen‐containing heterocycles in pharmacological applications , and in our progressive synthetic researches , we now become interested in a one‐pot MCR in which pyridine containing dihydropyrrolo core fused phenanthridines 5a–f in excellent yields can be obtained by reacting pyridinecarboxaldehydes 1 , alkylisocyanides 2 , and phenanthridine 4 in the presence of malononitrile 3 at ambient temperature (Scheme ).…”

Synthesis of Cyano-pyrrolo[1,2-a][1,10]phenanthroline Derivatives Using a Multicomponent Condensation

“…Proton shift and HCN elimination for aromatization occur as proposed in the mechanism shown in Scheme . Such a mechanism is consistent with the general structure of compound 5a and is supported by spectroscopic data.…”

Synthesis of 1‐(Cyclohexylamino)‐2‐(aryl)pyrrolo[1,2‐a]quinoline‐3‐carbonitrile Derivatives Using a Mild, Four‐Component Reaction

“…Because of the aforementioned finding and as a part of our ongoing research program on the IMCRs , we report herein the synthesis of substituted 1‐(cyclohexylamino)‐2‐(aryl)pyrrolo[1,2‐a]quinoline‐3‐carbonitrile derivatives 5 by a four‐component condensation reaction (Scheme ).…”