Hydroxyaldehyde products from hydroxyl radical reactions of Z-3-hexen-1-ol and 2-methyl-3-buten-2-ol quantified by SPME and API-MS.
Hydroxyaldehyde products of the OH radical-initiated reactions (in the presence of NO) of two volatile vegetative emissions, Z-3-hexen-1-ol and 2-methyl-3-buten-2-ol, were examined to assess the qualitative and quantitative potential of two analysis techniques (1) sampling by Solid-Phase MicroExtraction (SPME) with on-fiber derivatization followed by gas chromatographic analyses and (2) in situ analysis by negative ion mode atmospheric pressure ionization mass spectrometry (API-MS). The compounds were chosen because reaction mechanisms predict hydroxyaldehyde products, and reliable coproduct yield data are available. The API-MS analyses showed product ion peaks attributed to the NO2- adducts of 3-hydroxypropanal and dihydroxynitrates from Z-3-hexen-1-ol, and a formation yield of 3-hydroxypropanal of 44% was derived. Product ion peaks attributed to NO2- adducts of glycolaldehyde [HOCH2CHO], 2-hydroxy-2-methylpropanal [(CH3)2C(OH)CHO], and dihydroxynitrates were observed by API-MS from 2-methyl-3-buten-2-ol, and a formation yield of 2-hydroxy-2-methylpropanal of 16% was obtained. In experiments with SPME sampling, the formation yields of hydroxycarbonyls measured as their oxime derivatives were as follows: from Z-3-hexen-1-ol, propanal, 56 +/- 8%; 3-hydroxypropanal, 101 +/- 24%; and from 2-methyl-3-buten-2-ol, 2-hydroxy-2-methylpropanal, 31 +/- 4%. Both the API-MS and SPME analyses provided product information, and hydroxycarbonyl yields from the SPME data are in reasonable agreement with previously measured formation yields of coproducts.
Air Pollution Research Center, University of California, Riverside, California 92521, USA.
Fabienne
F
Reisen
Sara M
SM
Aschmann
Roger
R
Atkinson
Janet
J
Arey
D002623:Chemistry Techniques, Analytical / Q000379:methods; D000441:Hexanols / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry*; D013058:Mass Spectrometry; D016877:Oxidants / Q000737:chemistry*; D000439:Pentanols / Q000737:chemistry*; D014835:Volatilization
D000441:Hexanols; D016877:Oxidants; D000439:Pentanols; C051918:3-hexen-1-ol; D017665:Hydroxyl Radical; C027250:3-hydroxy-3-methylbutene