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Updated: Dec 21, 2025

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Integration of ion exchange resin materials for a downstream-processing approach of an imine reductase-catalyzed
Lars-Erik Meyer1, Henrike Brundiek2, Jan von Langermann1
1Biocatalytic Synthesis Group, Institute of Chemistry, University of Rostock, Rostock, Germany.
Abstract:
In this study, an ion exchange resin-based downstream-processing concept for imine reductase (IRED)-catalyzed reactions was investigated. As a model reaction, 2-methylpyrroline was converted to its corresponding product (S)-2-methylpyrrolidine with >99% of conversion by the (S)-selective IRED from Paenibacillus elgii B69. Under optimized reaction conditions full conversion was achieved using a substrate concentration of 150 and 500 mmol/L of d-glucose. Seven commercially available cation- and anion-exchange resins were studied with respect to their ability to recover the product from the reaction solution. Without any pretreatment, cation-exchange resins Amberlite IR-120(H), IRN-150, Dowex Monosphere 650C, and Dowex Marathon MSC showed high recovery capacities (up to >90%). A 150-ml preparative scale reaction was performed yielding ~1 g hydrochloride salt product with >99% purity. Any further purification steps, for example, by column chromatography or recrystallization, were not required.
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