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Updated: Jun 2, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Water-Mediated Arylation of an Imine Intermediate: A Catalyst- and Promoter-Free Three-Component Coupling in a Mortar
1Graduate School of Pharmaceutical Sciences, The University of Osaka, Yamada-oka Suita, Osaka 565-0871, Japan.
Abstract:
This paper describes solvent-free three-component coupling reactions in a mortar. The coupling of the water-insoluble aldehydes and alkylamines with resorcinol provided N-alkylmethyl-substituted resorcinols. The three-component coupling reaction was carried out at room temperature in the absence of a solvent, without a specific catalyst or promoter. The aldimine was initially produced by the dehydration of alkanal and primary amine, followed by arylation with resorcinol, which resulted in the formation of the coupling product. The reaction of the isolated imine with resorcinol revealed that the addition of a small amount of water is essential during the coupling process. The presence of a water molecule generated by the dehydration of the aldehyde and amine promoted the formation of new C-C bonds. On the basis of the experimental finding, the reaction mechanism is proposed.
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