Intermolecular Carbanion Attack on Nitro vs. Carbonyl Group: Experimental and Computational Studies

Highly efficient one‐pot synthesis of a series of indeno[2,1‐b]quinolin‐6‐ones 10 and indolo[1,2‐b]isoquinoline‐6,12‐diones 12 is portrayed from easily accessible starting materials such as indan‐1‐ones 7 and 2‐nitrobenzaldehydes 9. The reaction mechanism studies by control experiments and computational analysis reveal that the reactions are initiated by attack of a conjugate base of indanones 7 to the aldehyde group or the adjacent nitro group of 2‐nitrobenzaldehydes 9 followed by intramolecular cyclization involving a second anion to furnish the appropriate products. The heterocyclic compounds were obtained in moderate to good yields.