Direct Reductive Amination of Aldehydes and Ketones with 2,4-Ionene-Based Borohydride Exchange Resin as a Novel Polymer-Supported Reducing Agent

Abstract

Direct reductive amination of aldehydes and ketones were accomplished efficiently using high-capacity, ionene-based, polymer-supported borohydride reagent in isopropyl alcohol at reflux under neutral conditions. The reagent is easily prepared by mixing aqueous solution of 2,4-ionene bromide with an alkaline solution of sodium borohydride at room temperature. The generality of reaction was established using both aliphatic and aromatic aldehydes, ketones, and amines.

Keywords:

• 2,4-ionene
• Aldehydes
• Borohydride exchange resin
• Ketones
• Reductive amination

ACKNOWLEDGMENT

Financial support of this work from the Research Council of Mazandaran University gratefully acknowledged.

Notes

^a All reactions were carried out under reflux, and the molar ratio of reagent/carbonyl compound/amine was 2/1/1.2.

^b All products were characterized spectroscopically (¹H NMR, IR) and showed physical and spectral data in accordance with their expected structure and by comparison with authentic samples.

^c Yields refer to pure isolated products.