Studies of the Pyrolysis of Hydroaromatic Compounds with an Emphasis on Reactions of Ortho-Quinodimethanes

摘要

The studies described herein are the results of questions raised concerning the pyrolysis of simple hydroaromatic compounds. A key compound within this group is tetralin which is presumed to thermally eject ethylene to produce ortho-quinodimethane, which then isomerizes to benzocyclobutene. It is also known that styrene is produced in this thermolysis and a possible source was hypothesized to be benzocyclobutene. Thus, in Part I we sought to delineate the mechanistic pathways operating in the isomerization of benzocyclobutene to styrene. In Part II, a further study of a reaction of ortho-quinodimethane was pursued, the reaction of hydrogen gas with the exocyclic diene system of ortho-quinodimethane. The subject matter of Part III again deals with an ortho-quinodimethane, in this case 2,3-dihydronaphthalene. We wished to determine its role in the formation of the products of the pyrolysis of tetralin. More specifically, we attempted to determine its place among its other C sub 10 H sub 10 isomers, 1,2-dihydronaphthalene and ortho-divinylbenzene. The last section deals with the effect that active pyrolysis packings have on the products and product distributions resulting from the pyrolysis of simple hydroaromatic compounds. We also wanted to determine to what extent the quartz chips used in our ''normal'' flash vacuum pyrolyses were influencing the chemistry which we observed. 114 refs., 15 figs., 27 tabs. (ERA citation 11:013819)