Scaling up of continuous-flow, microwave-assisted, organic reactions by varying the size of Pd-functionalized catalytic monoliths

He, Ping; Haswell, Stephen J.; Fletcher, Paul D.I.; Kelly, Stephen M.; Mansfield, Andrew

Abstract

A product-scalable, catalytically mediated flow system has been developed to perform Suzuki-Miyaura reactions under a microwave heating regime, in which the volumetric throughput of a Pd-supported silica monolith can be used to increase the quantity of the product without changing the optimal operating conditions. Two silica monoliths (both 3 cm long), with comparable pore diameters and surface areas, were fabricated with diameters of 3.2 and 6.4 mm to give volumetric capacities of 0.205 and 0.790 mL, respectively. The two monoliths were functionalized with a loading of 4.5 wt % Pd and then sealed in heat-shrinkable Teflon® tubing to form a monolithic flow reactor. The Pd-supported silica monolith flow reactor was then placed into the microwave cavity and connected to an HPLC pump and a backpressure regulator to minimize the formation of gas bubbles. The flow rate and microwave power were varied to optimize the reactant contact time and temperature, respectively. Under optimal reaction conditions the quantity of product could be increased from 31 mg per hour to 340 mg per hour simply by changing the volumetric capacity of the monolith. © 2011 He et al; licensee Beilstein-Institut.

Citation

He, P., Haswell, S. J., Fletcher, P. D., Kelly, S. M., & Mansfield, A. (2011). Scaling up of continuous-flow, microwave-assisted, organic reactions by varying the size of Pd-functionalized catalytic monoliths. Beilstein Journal of Organic Chemistry, 7, 1150-1157. https://doi.org/10.3762/bjoc.7.133

• Journal Article Type: Article
• Acceptance Date: Apr 2, 2011
• Online Publication Date: Aug 23, 2011
• Publication Date: Aug 23, 2011
• Publicly Available Date: May 1, 2018
• Journal: BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
• Print ISSN: 1860-5397
• Publisher: Beilstein-Institut
• Peer Reviewed: Peer Reviewed
• Volume: 7
• Pages: 1150-1157
• DOI: https://doi.org/10.3762/bjoc.7.133
• Keywords: Organic Chemistry
• Public URL: https://hull-repository.worktribe.com/output/405268
• Publisher URL: https://www.beilstein-journals.org/bjoc/articles/7/133