One-Pot Synthesis of Chromone-Fused Pyrrolo[2,1-a]isoquinolines and Indolizino[8,7-b]indoles: Iodine-Promoted Oxidative [2 + 2 + 1] Annulation of O-Acetylphenoxyacrylates with Tetrahydroisoquinolines and Noreleagnines

Abstract

An iodine-promoted one-pot cascade oxidative annulation reaction has been developed for the synthesis of chromone-fused-pyrrolo­[2,1-a]­isoquinolines and indolizino­[8,7-b]­indoles from o-acetylphenoxyacrylates, tetrahydroisoquinolines, and noreleagnines. This process underwent a logical approach to both chromone-fused-pyrrolo­[2,1-a]­isoquinolines and chromone-fused-indolizino­[8,7-b]­indoles isolamellarin derivatives. Manipulations of l-menthol and dl-α-tocopherol demonstrate the applications of this strategy.

Recent progress in the synthesis of pyrrolo[2,1-a]isoquinolines

“…Zhu, Wu and coworkers established an iodine-mediated one-pot synthesis of chromone-fused-pyrrolo[2,1- a ]isoquinolines with o -acetylphenoxyacrylates and tetrahydroisoquinolines by a logical design (Scheme 16). 28 A series of fundamental reactions including α-halogenation, oxidation, nucleophilic addition, 1,3-dipolar cycloaddition and oxidation were combined in a single reactor. Various electron-withdrawing or electron-donating groups can be tolerable, both on o -acetylphenoxyacrylates and tetrahydroisoquinolines.…”

Recent advances in the synthesis of chromenone fused pyrrolo[2,1-a]isoquinoline derivatives

“…Zhu et al 87 developed a molecular iodine-promoted one-pot cascade oxidative annulation reaction for the synthesis of 4 H -chromen-4-one (chromone) fused to the five-membered ring of dihydropyrrolo[2,1- a ]isoquinolines from o -acetylphenoxyacrylates and tetrahydroisoquinolines (Scheme 29). The protocol of the reactions involved consecutive α-halogenation, oxidation, nucleophilic addition, 1,3-dipolar cycloaddition, and oxidation.…”

Synthesis of Naphthoquinone‐ and Pyrrolo[2,1‐a]isoquinoline‐Fused Heterocycles and Tridemethoxy Lamellarin D

“…4). Recently, Wu and Zhu [9] have described the synthesis of ester-substituted chromone fused-pyrrolo[2,1-a]isoquinolines via iodine-promoted oxidative [2 + 2 + 1] annulation of acetylphenoxyacrylates with tetrahydroisoquinolines (Scheme 1, Eq. 5).…”