Synlett 2022; 33(03): 207-223
DOI: 10.1055/s-0040-1719830
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Domino Reactions of Chromones with Heterocyclic Enamines

Peter Langer
a   Institut für Chemie, Universität Rostock, Albert-Einstein-Str. 3a, 18059 Rostock, Germany
b   Leibniz-Institut für Katalyse e. V. an der Universität Rostock, ­Albert-Einstein-Str. 29a, 18059 Rostock, Germany
› Institutsangaben


Dedicated to Dr. Jorge Jios on the occasion of his 60th birthday

Abstract

Domino reactions of heterocyclic enamines with chromone derivatives provides a convenient synthesis of a great variety of annulated heterocyclic ring systems. The course of the reaction depends on the type of substituent located at position 3 of the chromone. Reactions of 3-unsubstituted chromones, 3-nitrochromones, and 3-halochromones proceed by conjugate addition of the carbon atom of the enamine to carbon C-2 of the chromone, ring cleavage, and recyclization via the chromone carbonyl group. In the case of 3-formylchromes, 3-dichloroacetylchromone, 3-perfluoroalkanoylthiochromones, 3-(2-fluorobenzoyl)chromones, and 3-methoxalylchromones the final cyclization proceeds via the carbonyl group located outside the chromone moiety. The functional groups located at the carbonyl group at position 3 of the chromone allow for further synthetic transformations including additional ring closures.

Contents

1 Introduction

2 3-Unsubstituted Chromones

3 3-Nitrochromones

4 3-Formylchromes

5 3-Dichloroacetylchromone

6 3-Perfluoroalkanoylthiochromones

7 3-Methoxalylchromones

8 3-(2-Fluorobenzoyl)chromones

9 3-Halochromones

10 Chromone-3-carboxylic Acids

11 Conclusions



Publikationsverlauf

Eingereicht: 29. Juli 2021

Angenommen nach Revision: 11. August 2021

Artikel online veröffentlicht:
02. September 2021

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