Application of benzophenones to elucidate the photochemical reaction pathways of hydrogen peroxide with dimethylsulfoxide |
| |
Authors: | J. R. Woodward T. -S. Lin Y. Sakaguchi H. Hayashi |
| |
Affiliation: | (1) Department of Chemistry, University of Utah, 315 South 1400 East, Room 2020, Salt Lake City, UT 84112-0850, USA; |
| |
Abstract: | Benzophenone ((C6H5)2CO) and decafluorobenzophenone ((C6F5)2CO) were applied to elucidate the photochemical reaction pathway of hydrogen peroxide (H2O2) with dimethylsulfoxide (DMSO). When a solution of benzophenone in DMSO was excited with the 355 nm laser light, three transient species were observed in the time-resolved electron paramagnetic resonance spectra: benzophenone ketyl (C6H5)2COH⋅, methyl⋅CH3, and methylsulfinic methyl⋅CH2SOCH3 radicals. However, when decafluoro-benzophenone was used with DMSO, only ketyl and methylsulfinic methyl radicals were observed under the same experimental conditions. When the reaction of benzophenone and DMSO was carried out in the presence of H2O2, different time profiles of⋅CH3 radicals were observed. In the reaction of decafluorobenzophenone-DMSO-H2O2, the time profiles of the radicals were not affected by the presence of H2O2. Thus, these results verify that⋅CH3 radicals are regenerated in a cyclic pathway, in which⋅CH3 radicals attack H2O2. The regeneration pathway allows us to observe f-pair polarization throughout the lifetime of⋅CH3 radicals, which last several microseconds, an order of magnitude longer than theT 1 relaxation time of⋅CH3 radicals. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|