Intramolecular Reductive Amidation of Unactivated Esters with Nitroarenes: A Telescoped Synthesis of Tetrahydropyrrolo/Pyrido[1,2‑a]quinoxalinones

A reductive amidation of unactivated esters with nitroarenes, a key step in the telescopic synthesis of tetrahydropyrrolo­[1,2-a]­quinoxalinones and tetrahydropyrido­[1,2-a]­quinoxalinones, is reported. The process involves an intermolecular base-mediated SNAr reaction, followed by intramolecular re...

Full description

Saved in:
Bibliographic Details
Published in:Journal of organic chemistry Vol. 89; no. 15; pp. 11053 - 11059
Main Authors: Hazra, Amitava, Laha, Joydev K.
Format: Journal Article
Language:English
Published: United States American Chemical Society 02-08-2024
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A reductive amidation of unactivated esters with nitroarenes, a key step in the telescopic synthesis of tetrahydropyrrolo­[1,2-a]­quinoxalinones and tetrahydropyrido­[1,2-a]­quinoxalinones, is reported. The process involves an intermolecular base-mediated SNAr reaction, followed by intramolecular reductive amidation employing sodium dithionite. The substrate scope coupled with the demonstration of the synthesis of pharmaceuticals is reported. The key features include nitro reduction at room temperature, easy purification without chromatography, amidation of unactivated esters without any externally added activating agent, and a telescopic process.
ISSN:0022-3263
1520-6904
DOI:10.1021/acs.joc.4c01129