Summary and Conclusion

In this contribution we presented the process development of the IRED-catalyzed synthesis of (S )‑2‑methylpyrrolidine with a special emphasis on an ion exchange-based downstream-processing approach. The biocatalytic reaction was partly optimized resulting in a substrate concentration of 150 mmol·L-1 and 500 mmol·L-1 of d‑glucose at 30 °C for 24 h. Additionally, a variety of adsorbent resins for the effective removal of both product and substrate from the reaction solution were investigated and Amberlite IR-120(H), IRN-150, Dowex Monosphere 650C and Dowex Marathon MSC were found to be the most effective cation exchange resins. After further studies, the resin Dowex Monosphere 650C was successfully used for the downstream-processing of a scaled up reaction to produce highly pure (>99%) (S )‑2‑methylpyrrolidine without any further purification steps. The developed process concept in this study, namely the integration of ion exchange resin materials into downstream-processing, is efficient and very simple to perform.