Synthesis 2023; 55(20): 3272-3280
DOI: 10.1055/s-0042-1751976
paper

Green Synthesis of Five-Membered Hetarene N-Oxides: A Designed Approach to the Synthesis of Substituted Chromeno[3,4-c]pyrrole-2-oxides

Abdolali Alizadeh
,
Azar Rostampoor
,
Hamidreza Hasanpour
We are grateful to the Research Council of Tarbiat Modares University for support of this work.


Abstract

An efficient and chemoselective synthesis of biologically valuable chromeno[3,4-c]pyrrole 2-oxides containing one chiral stereocenter is described. In this method, by using a sequential nucleophilic addition reaction involving coumarins (α,β-unsaturated coumarins or 3-acetylcoumarins), activated acetylenic compounds, triphenylphosphine as a catalyst, and hydroxylammonium chloride (HAC) as an NO source, substituted chromeno[3,4-c]pyrrole 2-oxides were prepared with excellent efficiency. Readily available starting materials, absence of a metal catalyst, green and mild conditions, chemoselectivity, easy purification (the products can be purified by simple filtration and washing with EtOH), and synthetically useful yields are some highlighted advantages of this unprecedented transformation.

Supporting Information



Publikationsverlauf

Eingereicht: 30. Januar 2023

Angenommen nach Revision: 07. Juni 2023

Artikel online veröffentlicht:
21. August 2023

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