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Updated: Jun 24, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Synthesis of 2-alkyl-substituted chromone derivatives using microwave irradiation
Maria Fridén-Saxin1, Nils Pemberton, Krystle da Silva Andersson
1Department of Chemistry, Medicinal Chemistry, University of Gothenburg, SE-41296 Goteborg, Sweden.
Abstract:
A base-promoted condensation between 2-hydroxyacetophenones and aliphatic aldehydes has been studied. The reaction has been optimized to afford 2-alkyl-substituted 4-chromanones in an efficient manner using microwave heating. Performing the reaction using diisopropylamine in EtOH at 170 degrees C for 1 h gave moderate to high yields (43-88%). The 4-chromanones could be further converted into highly functionalized 2,3,6,8-tetrasubstituted chromones in which a 3-substituent (acetate, amine, or bromine) was introduced via straightforward chemical transformations.
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