Abstractmagnified imageNew fused indeno[1,2‐b]pyridine derivatives have been prepared in a multicomponent reaction from benzaldehydes, indanedione and the appropriate aminoheteroaryl compound. The simple methodology permitted the syntheses of a series of indeno[1,2‐b]pyrazolo[4,3‐e]pyridines 4 from 5‐aminopyrazol 1 and modulated by the corresponding benzaldehyde 2.
Pyrazolo-fused 4-azafluorenones as key reagents for the synthesis of fluorescent dicyanovinylidene-substituted derivatives
4-azafluorenones (indeno[1,2-b]pyrazolo[4,3-e]pyridines, IPP) 4a–x via the three-component reaction between indan-1,3-dione (1), benzaldehydes 2 and 5-amino-1-arylpyrazoles 3 is described. These compounds were successfully used as precursors of the novel dicyanovinylidene derivatives 7a–d containing different acceptor (A) or donor (D) aryl groups at position 4 of its fused system. The structures of products