Specbrightspec.com/wp-content/uploads/Gloss-Direct-Chiral...composition of the essential oils of...
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© 2015 BrightSpec, Inc. 770 Harris St. Suite 104B, Charlottesville, VA 22903 www.brightspec.com Molecular rotational spectroscopy provides a spectral signature with extreme sensitivity to the mass distribution (3D structure) of the molecule. Instruments for measuring rotational spectra using pulsed jet sources offer high sensitivity and high spectral resolution. As a result, it is possible to perform direct quantitative analysis of complex mixtures without chromatographic separation. For samples that include chiral molecules, rotational spectroscopy can identify diastereomers of molecules with multiple chiral centers and, with fundamental advances in the past two years*, can perform enantiomeric excess measurements on the diastereomers. *David Patterson, Melanie Schnell, John M. Doyle, “Enantiomer-specific detection of chiral molecules via microwave spectroscopy”, Nature 497, 475 (2013). Broadband Rotational Spectrum of the Volatile Head Space (65˚C) 770 Harris St. Suite 104B, Charlottesville, VA 22903 www.brightspec.com Spec Molecular Rotational Resonance Spectroscopy Direct Chiral Analysis of Complex Mixtures by FT-MRR Spectroscopy Luca Evangelisti, Nathan Seifert, Lorenzo Spada, and Brooks H. Pate, Department of Chemistry, University of Virginia Matt Muckle, Justin Neill, and Roger Reynolds, BrightSpec, Inc., Charlottesville, VA Identification of the Diastereomers of 8-mercaptomenthone M. Sandasi, G.P.P. Kamatou, M. Baranska, and A.M. Viljoen, “Application of vibrational spectroscopy in the quality assessment of Buchu oil obtained from two commercially important Agathosma species (Rutaceae)”, South African J. of Botany 76, 692-700 (2010). Buchu Oil (betulina) Buchu Oil (crenulata) Z-8-mercaptomenthone E-8-mercaptomenthone
Transcript of Specbrightspec.com/wp-content/uploads/Gloss-Direct-Chiral...composition of the essential oils of...
© 2015 BrightSpec, Inc. 770 Harris St. Suite 104B, Charlottesville, VA 22903 www.brightspec.com
Molecular rotational spectroscopy provides a spectral signature with extreme sensitivity to the mass distribution (3D structure) of the molecule. Instruments for measuring rotational spectra using pulsed jet sources offer high sensitivity and high spectral resolution. As a result, it is possible to perform direct quantitative analysis of complex mixtures without chromatographic separation. For samples that include chiral molecules, rotational spectroscopy can identify diastereomers of molecules with multiple chiral centers and, with fundamental advances in the past two years*, can perform enantiomeric excess measurements on the diastereomers.
*David Patterson, Melanie Schnell, John M. Doyle, “Enantiomer-specific detection of chiral molecules via microwave spectroscopy”, Nature 497, 475 (2013).
Broadband Rotational Spectrum of the Volatile Head Space (65˚C)
770 Harris St. Suite 104B, Charlottesville,VA 22903www.brightspec.com
SpecMolecular Rotational Resonance Spectroscopy
Direct Chiral Analysis of Complex Mixturesby FT-MRR SpectroscopyLuca Evangelisti, Nathan Seifert, Lorenzo Spada, and Brooks H. Pate, Department of Chemistry, University of VirginiaMatt Muckle, Justin Neill, and Roger Reynolds, BrightSpec, Inc., Charlottesville, VA
Identification of the Diastereomers of 8-mercaptomenthone
M. Sandasi, G.P.P. Kamatou, M. Baranska, and A.M. Viljoen, “Application of vibrational spectroscopy in the quality assessment of Buchu oil obtained from two commercially important Agathosma species (Rutaceae)”, South African J. of Botany 76, 692-700 (2010).
Buchu Oil (betulina)
Buchu Oil (crenulata)
Z-8-mercaptomenthone
E-8-mercaptomenthone
© 2015 BrightSpec, Inc. 770 Harris St. Suite 104B, Charlottesville, VA 22903 www.brightspec.com
Three Conformations of Menthone
This work supported by BrightSpec, NSF MRI CHE-0960074, University of Bologna (LS), and ERS/EU Marie Curie Postdoctoral Research Fellowship Program (LE)
D. Schmitz, V.A. Schubert, T. Betz, and M. Schnell, “Exploring the conformational landscape of menthol, menthone, and isomenthone: a microwave study”, Frontiers in Chemistry 3, Article 15 (2015).
M. A. Posthumus, T. A. van Beek, N. F. Collins and E. H. Graven, “Chemical composition of the essential oils of Agathosma betulina, A. crenulata and an A. betulina x crenulata hybrid (buchu)”, J. Essent, Oil Res., 8, 223-228 (1996).
Acknowledgements
Direct Chiral Analysis of Complex Mixtures by FT-MRR Spectroscopy
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B3LYP/6-311++(d,p)
Enantiomeric Excess Measurement of Menthone Directly in the Mixture using Three Wave Mixing FT-MRR Spectroscopy
Initial Analysis of Buchu Oil Composition
Diosphenol 22 • •
Isomethone 20 • •
4-diosphenol 19 • •
Limonene 12 • •
Menthone 10 • •
1,8-cineole 4 • •
Z-8-mercaptomenthone 2 • •
Pulegone 1 •
E-isopulegone 0.5 • •
E-8-mercaptomenthone 0.5 • •
Linalool 0.5 •
α-pinene 0.4 • •
Z-isopulegone 0.4 • •
β-pinene 0.3 • •
Piperitone 0.06 • •
Molecule % Assigned in MixtureObs Previous
MW AnalysisReferenceSpectrum
S. Lobsiger, C. Perez, L. Evangelisti, K. K. Lehmann, B. H. Pate, “Molecular Structure and Chirality Detection by Fourier Transform Microwave Spectrosco-py”, J. Phys. Chem. Lett. 6, 196-200 (2015).
