Evaluation of a Nonresonant Microwave Applicator for Continuous-Flow Chemistry Applications
2012 (English)In: Organic Process Research & Development, ISSN 1083-6160, E-ISSN 1520-586X, Vol. 16, no 5, 1053-1063 p.Article in journal (Refereed) Published
The concept of a nonresonant microwave applicator for continuous-flow organic chemistry is introduced and evaluated. The frequency of the incident microwave radiation can be adjusted between 2.4 and 2.5 GHz to optimize the energy absorbance. The temperature of the reaction is monitored by five IR sensors, and their signals can be used to automatically adjust the power output from the microwave generator. The heating of several different solvents up to 20 degrees C above the standard boiling point has been explored. Several different organic reactions have been successfully carried out using a 200 mm X (sic) 3 mm tubular borosilicate reactor and a flow between 47 and 2120 mu L/min. The microwave heating pattern was visualized with an IR camera. The transformations include palladium-catalyzed coupling reactions (oxidative Heck and Suzuki reactions), heterocyclic chemistry (oxathiazolone and Fischer indole synthesis), rearrangement (Claisen), and a Diels-Alder cycloaddition reaction. A scale-out to 57 mmol/h was performed with the Fischer indole reaction.
Place, publisher, year, edition, pages
2012. Vol. 16, no 5, 1053-1063 p.
non-resonant, microwave, Continuous-Flow, MAOS, CF-MAOS
Medicinal Chemistry Organic Chemistry
Research subject Medicinal Chemistry
IdentifiersURN: urn:nbn:se:uu:diva-160187DOI: 10.1021/op300003bISI: 000304129100036OAI: oai:DiVA.org:uu-160187DiVA: diva2:448674