Investigation of resonantly selected Raman spectra of intermediates in organic pyrolysis reactions
Abbreviated Journal Title
J. Raman Spectrosc.
NITROSOKETENE INTERMEDIATE; MELDRUMS ACID; NITRONES; EXCHANGE; DENSITY; Spectroscopy
The usefulness of UV resonance Raman (UVRR) spectroscopy in determining intermediate configurations in pyrolysis reactions was examined. We investigated the conformations of the nitrosoketene, E- and Z-isomers, generated via the pyrolysis of isonitroso Meldrum's acid by their characteristic vibrational wavenumbers. In this system, UVRR with 355 nm excitation worked exceptionally well to enhance selectively the nitrosoketene peaks. The signal was virtually free from other intermediates interferences, which was a major problem in IR spectroscopy. While both E- and Z-nitrosoketene were found as the intermediates of the isonitroso Meldrum's acid pyrolysis by UVRR, we consider that the observation of two isomers is due to their interconversions at 150degreesC, based upon computational analysis. Therefore, spectroscopic information on a shorter time-scale is necessary to determine the intermediate configuration in pyrolysis reactions. This method will still be useful for monitoring reactions at low temperatures, which may not involve significant interconversions of isomers. Copyright (C) 2002 John Wiley Sons, Ltd.
Journal of Raman Spectroscopy
"Investigation of resonantly selected Raman spectra of intermediates in organic pyrolysis reactions" (2002). Faculty Bibliography 2000s. 3353.