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Abstract Biocatalytic processes are highly selective and specific. However, their utility is limited by the comparatively narrow scope of enzyme‐catalysed transformations. To expand product scope, we are developing biocompatible processes that combine biocatalytic reactions with chemo‐catalysis in single‐flask processes. Here, we show that a chemocatalysed Pictet‐Spengler annulation can be interfaced with biocatalysed alcohol oxidation. This two‐step, one‐pot cascade reaction converts tyramine and aliphatic alcohols to tetrahydroisoquinoline alkaloids in aqueous buffer at mild pH. Tryptamine derivatives are also efficiently converted to tryptolines. Optimization of stoichiometry, pH, reaction time, and whole‐cell catalyst deliver the tetrahydroisouinolines and tryptolines in >90 % and >40 % isolated yield, respectively, with excellent regioselectivity.
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Catalytic Reaction Triggered by Magnetic Induction Heating Mechanistically Distinguishes Itself from the Standard Thermal Reaction
As a recent advancement in reaction engineering, magnetic induction heating (MIH) is utilized to initiate the intended reactions by enabling the self-heating of the ferromagnetic catalyst particles. While MIH can be energy-efficient and industrially scalable, its full potential has been underappreciated in catalysis because of the perception that MIH is merely an alternative heating approach. Unexpectedly, we show that the MIH-triggered reaction could go beyond standard thermal catalysis. Specifically, by probing the representative Pt/Fe3O4 catalysts with CO oxidation in both thermal and MIH modes with consistent temperature profiles and catalyst structures, we found that the MIH mode boosts the reactivity more than 25 times by modifying Pt−FeOx interfacial synergies and promoting facile oxidation of the adsorbed carbonyl species by atomic oxygen. As we preliminarily observed, this beneficial MIH catalysis can be translational to other thermal reactions, potentially paving the way to launch MIH catalysis as a distinct reaction category.
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- Award ID(s):
- 2146591
- PAR ID:
- 10554420
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Catalysis
- Volume:
- 14
- Issue:
- 6
- ISSN:
- 2155-5435
- Page Range / eLocation ID:
- 4008 to 4017
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1021/acscatal.3c05989
