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Title: Accelerated thermal reaction kinetics by indirect microwave heating of a microwave-transparent substrate
Macroscopically homogeneous mixtures of p -nitroanisole ( p NA) and mesitylene (MES) can be selectively heated using microwave (MW) energy. The p NA solutes agglomerate into distinct phase domains on the attoliter-scale (1 aL = 10 −18 L), and these agglomerates can be MW-heated selectively to temperatures that far exceed the boiling point of the surrounding MES solvent. Here, a 1 : 20 mixture of p NA : MES is used as a mixed solvent for aryl Claisen rearrangement of allyl naphthyl ether (ANE). ANE itself does not heat effectively in the MW, but selective MW heating of p NA allows for transfer of thermal energy to ANE to accelerate rearrangement kinetics above what would be expected based on Arrhenius kinetics and the measured bulk solution temperature. This focused study builds on prior work and highlights 1 : 20 p NA : MES as a mixed solvent system to consider for strategically exploiting MW-specific thermal effects.
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Physical Chemistry Chemical Physics
Page Range or eLocation-ID:
2794 to 2799
Sponsoring Org:
National Science Foundation
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