Header

UZH-Logo

Maintenance Infos

Thermisches Verhalten von 1,2-Dipropenylbenzolen


Heimgartner, Heinz; Hansen, Hans-Jürgen; Schmid, Hans (1972). Thermisches Verhalten von 1,2-Dipropenylbenzolen. Helvetica Chimica Acta, 55(5):1385-1403.

Abstract

1-cis,2-cis-Dipropenylbenzene (cis,cis-1) isomerises thermally at 215-235° with 1st order kinetics to give trans,cis-1, and vice versa. At equilibrium 89% trans,cis- and 11% cis,cis-1 are present. It is shown by thermal rearrangement of cis,cis-2', 2"-d2-1 that the isomerisation is attributable to aromatic [1,7a]-sigmatropic H-shifts. trans,trans-1 rearranges thermally at 225-245° to yield 2,3-dimethyl-1,2-dihydronaphthalene (2). The formation of 2 can be visualized by disrotatory ring closure followed by an aromatic [1, 5s]-sigmatropic H-shift. 2 is also formed when cis,cis- or trans,cis-1 are heated for 153 h a t 225°. Besides 2 a small amount (3%) of 1-ethyl-1,2-dihydronaphthalene (5) is formed. The rearrangement of trans, trans-1 and trans, trans-2'.2"- d2-1 shows a secondary isotope effect kH/kD = 0.90.

Abstract

1-cis,2-cis-Dipropenylbenzene (cis,cis-1) isomerises thermally at 215-235° with 1st order kinetics to give trans,cis-1, and vice versa. At equilibrium 89% trans,cis- and 11% cis,cis-1 are present. It is shown by thermal rearrangement of cis,cis-2', 2"-d2-1 that the isomerisation is attributable to aromatic [1,7a]-sigmatropic H-shifts. trans,trans-1 rearranges thermally at 225-245° to yield 2,3-dimethyl-1,2-dihydronaphthalene (2). The formation of 2 can be visualized by disrotatory ring closure followed by an aromatic [1, 5s]-sigmatropic H-shift. 2 is also formed when cis,cis- or trans,cis-1 are heated for 153 h a t 225°. Besides 2 a small amount (3%) of 1-ethyl-1,2-dihydronaphthalene (5) is formed. The rearrangement of trans, trans-1 and trans, trans-2'.2"- d2-1 shows a secondary isotope effect kH/kD = 0.90.

Statistics

Citations

32 citations in Web of Science®
26 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

0 downloads since deposited on 29 Dec 2014
0 downloads since 12 months

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Chemistry
Dewey Decimal Classification:540 Chemistry
Language:German
Date:1972
Deposited On:29 Dec 2014 15:08
Last Modified:05 Apr 2016 18:39
Publisher:Wiley-Blackwell Publishing, Inc.
ISSN:0018-019X
Funders:Schweizerischer Nationalfonds
Publisher DOI:https://doi.org/10.1002/hlca.19720550505

Download

Preview Icon on Download
Content: Published Version
Filetype: PDF - Registered users only
Size: 1MB
View at publisher

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.

Author Collaborations