Olefin Autoxidation in Flow

• Main Authors: Neuenschwander, Ulrich (Contributor), Jensen, Klavs F. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Chemical Engineering (Contributor)
• Format: Article
• Language: English
• Published: American Chemical Society (ACS), 2015-01-22T21:29:38Z.
• Subjects: Article
• Online Access: Get fulltext

 Handling hazardous multiphase reactions in flow brings not only safety advantages but also significantly improved performance, due to better mass transfer characteristics. In this paper, we present a continuous microreactor setup, capable of performing olefin autoxidations with O[subscript 2], under solvent-free and catalyst-free conditions. Owing to the transparent reactor design, consumption of O[subscript 2] can be visually followed and exhaustion of the gas bubbles marks a clear end point along the channel length coordinate. Tracking the position of this end point enables measuring effective rate constants. The developed system was calibrated using the well-studied β-pinene substrate, and was subsequently applied to the synthetically interesting transformation of (+)-valencene to (+)-nootkatone. For the latter, a space-time yield was obtained that is at least 3 orders of magnitude larger than that realized with established biotechnology approaches.