Solvent-dependent complex reaction pathways of bromoform revealed by time-resolved X-ray solution scattering and X-ray transient absorption spectroscopy
(2019) In Structural Dynamics 6(6).- Abstract
The photochemical reaction pathways of CHBr3 in solution were unveiled using two complementary X-ray techniques, time-resolved X-ray solution scattering (TRXSS) and X-ray transient absorption spectroscopy, in a wide temporal range from 100 ps to tens of microseconds. By performing comparative measurements in protic (methanol) and aprotic (methylcyclohexane) solvents, we found that the reaction pathways depend significantly on the solvent properties. In methanol, the major photoproducts are CH3OCHBr2 and HBr generated by rapid solvolysis of iso-CHBr2-Br, an isomer of CHBr3. In contrast, in methylcyclohexane, iso-CHBr2-Br returns to CHBr3 without solvolysis. In... (More)
The photochemical reaction pathways of CHBr3 in solution were unveiled using two complementary X-ray techniques, time-resolved X-ray solution scattering (TRXSS) and X-ray transient absorption spectroscopy, in a wide temporal range from 100 ps to tens of microseconds. By performing comparative measurements in protic (methanol) and aprotic (methylcyclohexane) solvents, we found that the reaction pathways depend significantly on the solvent properties. In methanol, the major photoproducts are CH3OCHBr2 and HBr generated by rapid solvolysis of iso-CHBr2-Br, an isomer of CHBr3. In contrast, in methylcyclohexane, iso-CHBr2-Br returns to CHBr3 without solvolysis. In both solvents, the formation of CHBr2 and Br is a competing reaction channel. From the structural analysis of TRXSS data, we determined the structures of key intermediate species, CH3OCHBr2 and iso-CHBr2-Br in methanol and methylcyclohexane, respectively, which are consistent with the structures from density functional theory calculations.
(Less)
- author
- publishing date
- 2019-11-01
- type
- Contribution to journal
- publication status
- published
- in
- Structural Dynamics
- volume
- 6
- issue
- 6
- article number
- 064902
- publisher
- American Institute of Physics (AIP)
- external identifiers
-
- scopus:85077303141
- pmid:31893214
- ISSN
- 2329-7778
- DOI
- 10.1063/1.5132968
- language
- English
- LU publication?
- no
- id
- 82969e4b-dc0a-4e6c-8bbc-6bccd216db35
- date added to LUP
- 2020-03-25 12:25:40
- date last changed
- 2024-07-10 13:17:23
@article{82969e4b-dc0a-4e6c-8bbc-6bccd216db35, abstract = {{<p>The photochemical reaction pathways of CHBr<sub>3</sub> in solution were unveiled using two complementary X-ray techniques, time-resolved X-ray solution scattering (TRXSS) and X-ray transient absorption spectroscopy, in a wide temporal range from 100 ps to tens of microseconds. By performing comparative measurements in protic (methanol) and aprotic (methylcyclohexane) solvents, we found that the reaction pathways depend significantly on the solvent properties. In methanol, the major photoproducts are CH<sub>3</sub>OCHBr<sub>2</sub> and HBr generated by rapid solvolysis of iso-CHBr<sub>2</sub>-Br, an isomer of CHBr<sub>3</sub>. In contrast, in methylcyclohexane, iso-CHBr<sub>2</sub>-Br returns to CHBr<sub>3</sub> without solvolysis. In both solvents, the formation of CHBr<sub>2</sub> and Br is a competing reaction channel. From the structural analysis of TRXSS data, we determined the structures of key intermediate species, CH<sub>3</sub>OCHBr<sub>2</sub> and iso-CHBr<sub>2</sub>-Br in methanol and methylcyclohexane, respectively, which are consistent with the structures from density functional theory calculations.</p>}}, author = {{Kong, Qingyu and Khakhulin, Dmitry and Shkrob, Ilya A. and Lee, Jae Hyuk and Zhang, Xiaoyi and Kim, Jeongho and Kim, Kyung Hwan and Jo, Junbeom and Kim, Jungmin and Kang, Jaedong and Pham, Van Thai and Jennings, Guy and Kurtz, Charles and Spence, Rick and Chen, Lin X. and Wulff, Michael and Ihee, Hyotcherl}}, issn = {{2329-7778}}, language = {{eng}}, month = {{11}}, number = {{6}}, publisher = {{American Institute of Physics (AIP)}}, series = {{Structural Dynamics}}, title = {{Solvent-dependent complex reaction pathways of bromoform revealed by time-resolved X-ray solution scattering and X-ray transient absorption spectroscopy}}, url = {{http://dx.doi.org/10.1063/1.5132968}}, doi = {{10.1063/1.5132968}}, volume = {{6}}, year = {{2019}}, }