Abstract
cis,cis-, cis,trans- and trans,trans-o-Dipropenylbenzene (cis,cis-, cis,trans- and trans,trans-1) were prepared. At 225° cis,cis-1 isomerises to give cis,trans-1 and vice versa. The isomerisation follows 1.order kinetics. At equilibrium 89% cis,trans- and 11% cis,cis-1 are present. It is shown by deuterium labelling that the isomerisation is due to aromatic [1,7a] sigmatropic H-shifts. trans,trans-1 rearranges at 225° to yield 2,3-dimethyl-1,2-dihydronaphthalene (3). This can be visualized by disrotatory ring closure of trans,trans-1 followed by an aromatic [1,5s] H-shift. When cis,cis- or cis,trans-1 are heated for 153 hrs a t 225° a small amount (3%) of 1-ethyl-1,2-dihydronaphthalene (5) is formed.
Abstract
cis,cis-, cis,trans- and trans,trans-o-Dipropenylbenzene (cis,cis-, cis,trans- and trans,trans-1) were prepared. At 225° cis,cis-1 isomerises to give cis,trans-1 and vice versa. The isomerisation follows 1.order kinetics. At equilibrium 89% cis,trans- and 11% cis,cis-1 are present. It is shown by deuterium labelling that the isomerisation is due to aromatic [1,7a] sigmatropic H-shifts. trans,trans-1 rearranges at 225° to yield 2,3-dimethyl-1,2-dihydronaphthalene (3). This can be visualized by disrotatory ring closure of trans,trans-1 followed by an aromatic [1,5s] H-shift. When cis,cis- or cis,trans-1 are heated for 153 hrs a t 225° a small amount (3%) of 1-ethyl-1,2-dihydronaphthalene (5) is formed.
Additional indexing
| Item Type: | Journal Article, refereed, original work |
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| Communities & Collections: | 07 Faculty of Science > Department of Chemistry |
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| Dewey Decimal Classification: | 540 Chemistry |
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| Uncontrolled Keywords: | Physical and Theoretical Chemistry, Inorganic Chemistry, Organic Chemistry, Biochemistry, Drug Discovery, Catalysis |
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| Language: | German |
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| Date: | 1970 |
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| Deposited On: | 29 Dec 2014 15:03 |
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| Last Modified: | 24 Sep 2019 20:42 |
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| Publisher: | Wiley-Blackwell Publishing, Inc. |
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| ISSN: | 0018-019X |
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| Funders: | Schweizerischer Nationalfonds |
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| OA Status: | Closed |
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| Publisher DOI: | https://doi.org/10.1002/hlca.19700530124 |
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Heimgartner, Heinz