59154-50-6Relevant academic research and scientific papers
Thermochemistry of Phenyl-Substituted Benzobicyclohex-2-enes
Lamberts, Joseph J.,Laarhoven, Wim H.
, p. 100 - 106 (2007/10/02)
The thermal rearrangements of benzobicyclohex-2-ene (21) and its phenyl-substituted analogues 22-25 (Scheme V) as models of sterically constrained phenylcyclopropanes have been studied by means of flash vacuum pyrolysis.In most cases the major pathway was cleavage of the "internal" C(1)-C(5) cyclopropane bond followed by a 1,2-hydrogen or a 1,2-phenylshift in the resulting biradical.For 6-phenylbenzobicyclohex-2-ene (25), substantial cleavage of the "external" C(1)-C(6) cyclopropane bond was observed, the phenyl substitution pattern being favorable for stabilization of the resulting biradical 62.Phenyl-substituted 1,2-dihydronaphthalenes 44, 47, 51, and 55 are among the major products.Comparison of the plots of the pyrolysis product composition of the 1,2-dihydronaphthalenes vs. pyrolysis temperature with similar plots of the title compounds (22-25) suggested that some of the minor products, viz., the 1,2-divinylbenzenes 31, 42, and 49, are formed via carbenes 30, 41, 50, 57, and 61 rather than via biradicals.Especially at higher pyrolysis temperatures, a large amount of an oxidation product, viz., 1- or 2-phenylnaphthalene (48 or 54), is formed.
