Scaling up of continuous-flow, microwave-assisted, organic reactions by varying the size of Pd-functionalized catalytic monoliths
| Autor: | Paul D. I. Fletcher, Stephen J. Haswell, Andrew C. Mansfield, Stephen M. Kelly, Ping He |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2011 |
| Předmět: |
geography
geography.geographical_feature_category Continuous flow Chemistry Organic Chemistry Flow (psychology) scaling-up microwave heating Nanotechnology Full Research Paper Volumetric flow rate Catalysis lcsh:QD241-441 Suzuki–Miyaura reaction Organic reaction Chemical engineering lcsh:Organic chemistry monolith continuous flow lcsh:Q Monolith lcsh:Science Scaling Microwave cavity |
| Zdroj: | Beilstein Journal of Organic Chemistry, Vol 7, Iss 1, Pp 1150-1157 (2011) Beilstein Journal of Organic Chemistry |
| ISSN: | 1860-5397 |
| Popis: | 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. |
| Databáze: | OpenAIRE |
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