284-22-0Relevant articles and documents
Secondary ozonides of substituted cyclohexenes: A new class of pollutants characterized by collision-induced dissociation mass spectrometry using negative chemical ionization
Norgaard, Asger W.,Nojgaard, Jacob K.,Clausen, Per A.,Wolkoff, Peder
, p. 2032 - 2038 (2008)
Recent studies indicate that secondary ozonides of cyclic alkenes are formed in atmospheric reactions and may be relatively stable. The secondary ozonides (SOZs) of cyclohexene (1), 1-methylcyclohexene (2), 4-isopropyl-1-methylcyclohexene (3) and 4-isopropenyl-1-methylcyclohexene (limonene) (4) have been characterized by rapid gas chromatography electron ionization (EI), negative and positive chemical ionization (CI: ammonia, isobutane and methane) and collision-induced dissociation (CID) mass spectrometry. Both EI and positive CI spectra were found unsuitable for reproducible analysis. However, negative CI showed stable (M-H)- ions with minor fragmentation. CID of the (M-H)- ions resulted in simple and reproducible fragmentation patterns for all four SOZs with loss of m/z 18, 44 and 60, tentatively assigned as H2O, CO2 and C2H4O2 or CO3, respectively. Thus, negative CI-MS-MS in combination with rapid gas chromatography is the preferred method for identification of secondary ozonides of cyclohexenes.