A Clock Reaction Based on Molybdenum Blue
Clock reactions are rare kinetic phenomena, so far limited mostly to systems with ionic oxoacids and oxoanions in water. We report a new clock reaction in cyclohexanol that forms molybdenum blue from a noncharged, yellow molybdenum complex as precursor, in the presence of hydrogen peroxide. Interest...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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American Chemical Society (ACS)
2015
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| Online Access: | http://hdl.handle.net/1721.1/92773 https://orcid.org/0000-0001-7192-580X |
| _version_ | 1811069086577197056 |
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| author | Neuenschwander, Ulrich Negron, Arnaldo Jensen, Klavs F. |
| author2 | Massachusetts Institute of Technology. Department of Chemical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Chemical Engineering Neuenschwander, Ulrich Negron, Arnaldo Jensen, Klavs F. |
| author_sort | Neuenschwander, Ulrich |
| collection | MIT |
| description | Clock reactions are rare kinetic phenomena, so far limited mostly to systems with ionic oxoacids and oxoanions in water. We report a new clock reaction in cyclohexanol that forms molybdenum blue from a noncharged, yellow molybdenum complex as precursor, in the presence of hydrogen peroxide. Interestingly, the concomitant color change is reversible, enabling multiple clock cycles to be executed consecutively. The kinetics of the clock reaction were experimentally characterized, and by adding insights from quantum chemical calculations, a plausible reaction mechanism was postulated. Key elementary reaction steps comprise sigmatropic rearrangements with five-membered or bicyclo[3.1.0] transition states. Importantly, numerical kinetic modeling demonstrated the mechanism’s ability to reproduce the experimental findings. It also revealed that clock behavior is intimately connected to the sudden exhaustion of hydrogen peroxide. Due to the stoichiometric coproduction of ketone, the reaction bears potential for application in alcohol oxidation catalysis. |
| first_indexed | 2024-09-23T08:05:29Z |
| format | Article |
| id | mit-1721.1/92773 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T08:05:29Z |
| publishDate | 2015 |
| publisher | American Chemical Society (ACS) |
| record_format | dspace |
| spelling | mit-1721.1/927732022-09-23T10:50:20Z A Clock Reaction Based on Molybdenum Blue Neuenschwander, Ulrich Negron, Arnaldo Jensen, Klavs F. Massachusetts Institute of Technology. Department of Chemical Engineering Jensen, Klavs F. Neuenschwander, Ulrich Negron, Arnaldo Jensen, Klavs F. Clock reactions are rare kinetic phenomena, so far limited mostly to systems with ionic oxoacids and oxoanions in water. We report a new clock reaction in cyclohexanol that forms molybdenum blue from a noncharged, yellow molybdenum complex as precursor, in the presence of hydrogen peroxide. Interestingly, the concomitant color change is reversible, enabling multiple clock cycles to be executed consecutively. The kinetics of the clock reaction were experimentally characterized, and by adding insights from quantum chemical calculations, a plausible reaction mechanism was postulated. Key elementary reaction steps comprise sigmatropic rearrangements with five-membered or bicyclo[3.1.0] transition states. Importantly, numerical kinetic modeling demonstrated the mechanism’s ability to reproduce the experimental findings. It also revealed that clock behavior is intimately connected to the sudden exhaustion of hydrogen peroxide. Due to the stoichiometric coproduction of ketone, the reaction bears potential for application in alcohol oxidation catalysis. Swiss National Science Foundation 2015-01-09T19:08:28Z 2015-01-09T19:08:28Z 2013-05 2013-04 Article http://purl.org/eprint/type/JournalArticle 1089-5639 1520-5215 http://hdl.handle.net/1721.1/92773 Neuenschwander, Ulrich, Arnaldo Negron, and Klavs F. Jensen. “A Clock Reaction Based on Molybdenum Blue.” The Journal of Physical Chemistry A 117, no. 21 (May 30, 2013): 4343–4351. https://orcid.org/0000-0001-7192-580X en_US http://dx.doi.org/10.1021/jp400879d The Journal of Physical Chemistry A Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Chemical Society (ACS) Prof. Jensen via Erja Kajosalo |
| spellingShingle | Neuenschwander, Ulrich Negron, Arnaldo Jensen, Klavs F. A Clock Reaction Based on Molybdenum Blue |
| title | A Clock Reaction Based on Molybdenum Blue |
| title_full | A Clock Reaction Based on Molybdenum Blue |
| title_fullStr | A Clock Reaction Based on Molybdenum Blue |
| title_full_unstemmed | A Clock Reaction Based on Molybdenum Blue |
| title_short | A Clock Reaction Based on Molybdenum Blue |
| title_sort | clock reaction based on molybdenum blue |
| url | http://hdl.handle.net/1721.1/92773 https://orcid.org/0000-0001-7192-580X |
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