Synthesis of 6H‐Isoindolo[2,1‐a]indol‐6‐ones Through Wittig Reaction and Tandem Reductive Cyclization–Lactamization

Abstract

A convenient and efficient two‐step route to 6H‐Isoindolo[2,1‐a]indol‐6‐ones has been developed starting from o‐nitrobenzaldehydes. The methodology involves Wittig reaction followed by tandem reductive cyclization–lactamization. A series of isoindoloindolones incorporating different substituents on the indole nucleus has been prepared.

Facile approaches toward the synthesis of 6H-isoindolo[2,1-α]indol-6-ones via palladium-catalyzed carbonylation with carbon monoxide

“…[3][4][5][6][7][8][9] For example, a two-step strategy starting from o-nitrobenzaldehydes through wittig reaction and tandem reductive cyclization-lactamization was established by Tilve et al (Scheme 2, route 1). 4 The synthesis of 2a can also be carried out via an intramolecular wittig reaction from ophthalimidobenzyl bromide (Scheme 2, route 2). 5 Griffiths et al reported a convenient route to 2a from 2-(N-phthaloyl)benzoic acid via β-ketophosphonates (Scheme 2, route 3).…”