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Updated: Apr 11, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Structure determination of trans-cinnamaldehyde by broadband microwave spectroscopy
Sabrina Zinn1, Thomas Betz, Chris Medcraft
1Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, D-22761 Hamburg, Germany. melanie.schnell@mpsd.mpg.de.
Abstract:
The rotational spectrum of trans-cinnamaldehyde ((E)-3-phenyl-2-propenal, C9H8O) was recorded by chirped-pulse Fourier transform microwave spectroscopy in the frequency range of 2-8.5 GHz. The odourant molecule is the essential component of cinnamon oil and causes the characteristic smell. The rotational signatures of two conformers were observed: s-trans-trans- and s-cis-trans-cinnamaldehyde. The rotational spectra of s-trans-trans-cinnamaldehyde and all of its (13)C-monosubstituted species in natural abundance were assigned and the corresponding carbon backbone structure was determined. The second conformer s-cis-trans-cinnamaldehyde is about 9 kJ mol(-1) higher in energy and could also be identified in the spectrum.
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