ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
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, 7 a] 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, 5 s] H-shift. When cis, cis- or cis, trans-1 are heated for 153 hrs at 225° a small amount (3%) of 1-ethyl-1,2-dihydronaphthalene (5) is formed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19700530124
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