Concerted HO2 elimination from alpha-Aminoalkylperoxyl free radicals : Experimental and theoretical evidence from the gas phase NH2 center dot CHCO2- + O-2 reaction

da Silva, G., Kirk, B. B., Lloyd, C., Trevitt, A. J., & Blanksby, Stephen J. (2012) Concerted HO2 elimination from alpha-Aminoalkylperoxyl free radicals : Experimental and theoretical evidence from the gas phase NH2 center dot CHCO2- + O-2 reaction. Journal of Physical Chemistry Letters, 3(7), pp. 805-811.

View at publisher

Abstract

We have investigated the gas-phase reaction of the α-aminoacetate (glycyl) radical anion (NH2CHCO2) with O2 using ion trap mass spectrometry, quantum chemistry, and statistical reaction rate theory. This radical is found to undergo a remarkably rapid reaction with O2 to form the hydroperoxyl radical (HO2) and an even-electron imine (NHCHCO2), with experiments and master equation simulations revealing that reaction proceeds at the ion–molecule collision rate. This reaction is facilitated by a low-energy concerted HO2 elimination mechanism in the NH2CH(OO)CO2 peroxyl radical. These findings can explain the widely observed free-radical-mediated oxidation of simple amino acids to amides plus α-keto acids (their imine hydrolysis products). This work also suggests that imines will be the main intermediates in the atmospheric oxidation of primary and secondary amines, including amine carbon capture solvents such as 2-aminoethanol (commonly known as monoethanolamine, or MEA), in a process that avoids the ozone-promoting conversion of NO to NO2 commonly encountered in peroxyl radical chemistry.

Impact and interest:

15 citations in Scopus
17 citations in Web of Science®
Search Google Scholar™

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

ID Code: 71646
Item Type: Journal Article
Refereed: Yes
Additional URLs:
Keywords: ab-initio, chemistry, kinetics, mechanism, oxidation, glycine, reactivity, dioxygen, ch2nh2, yields
DOI: 10.1021/jz300118k
ISSN: 1948-7185 (online)
Divisions: Current > Schools > School of Chemistry, Physics & Mechanical Engineering
Current > QUT Faculties and Divisions > Science & Engineering Faculty
Funding:
  • ACS/CE0561607
Copyright Owner: Copyright © 2012 American Chemical Society
Deposited On: 21 May 2014 01:40
Last Modified: 05 Sep 2016 23:20

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page