Meng-Xia Xu1, Lavrent Khachatryan1, Alexander Baev2, Rubik Asatryan2. 1. Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA. 2. Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
Abstract
The intermediate radicals produced in the gas-phase pyrolysis of one of the main building blocks of lignin - p-coumaryl alcohol (p-CMA) - were investigated using the low temperature matrix isolation technique interfaced with electron paramagnetic resonance spectroscopy (LTMI-EPR). An anisotropic EPR spectrum characterized by a high g-value (>2.0080) and a relatively low saturation coefficient (∼1.40) throughout the high pyrolytic temperature region (700 to 1000 °C) was observed. Theoretical calculations revealed plausible decomposition pathways for p-CMA comprising highly delocalized aromatic radicals. The results provide evidence for a dominant role of oxygen-centered radicals during the pyrolysis of p-CMA.
The intermediate radicals produced in the gas-phase pyrolysis of one of the main building blocks of n class="Chemical">lignin - p-coumaryl alcohol (p-CMA) - were investigated using the low temperature matrix isolation technique interfaced with electron paramagnetic resonance spectroscopy (LTMI-EPR). An anisotropic EPR spectrum characterized by a high g-value (>2.0080) and a relatively low saturation coefficient (∼1.40) throughout the high pyrolytic temperature region (700 to 1000 °C) was observed. Theoretical calculations revealed plausible decomposition pathways for p-CMA comprising highly delocalized aromatic radicals. The results provide evidence for a dominant role of oxygen-centered radicals during the pyrolysis of p-CMA.
Authors: Sanna Koutaniemi; Merja M Toikka; Anna Kärkönen; Maaret Mustonen; Taina Lundell; Liisa K Simola; Ilkka A Kilpeläinen; Teemu H Teeri Journal: Plant Mol Biol Date: 2005-05 Impact factor: 4.076
Authors: Rubik Asatryan; Hayat Bennadji; Joseph W Bozzelli; Eli Ruckenstein; Lavrent Khachatryan Journal: J Phys Chem A Date: 2017-04-26 Impact factor: 2.781