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Australian Journal of Chemistry Australian Journal of Chemistry Society
An international journal for chemical science
RESEARCH ARTICLE

Comparison of Conventional and Microwave Heating for Evaluation of Microwave Effects

Péter Bana A and István Greiner B C
+ Author Affiliations
- Author Affiliations

A Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, H-1521 Budapest, Hungary.

B Gedeon Richter Plc., H-1475 Budapest, PO Box 27, Hungary.

C Corresponding author. Email: i.greiner@richter.hu

Australian Journal of Chemistry 69(8) 865-871 https://doi.org/10.1071/CH16017
Submitted: 13 January 2016  Accepted: 16 February 2016   Published: 18 March 2016

Abstract

In microwave-assisted organic synthesis, the question of microwave effects is still debated. Proper examination of these hypothesized phenomena is encumbered by some specific features of microwave heating. We devise a convenient method to eliminate most of the irreproducibility observed in microwave-heated organic transformations by thermal conditioning of the microwave reactor cavity. To show the utility of this approach, we investigated a reaction of 2-chloropyridine, in which microwave conditions were shown to be beneficial by previous studies. Using our method to ensure proper reproducibility together with fibre optic temperature measurement, the observed differences were traced back to large hidden thermal differences, while non-thermal effects could not be detected in the comparison experiments.


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