Isomerization reactions of olefinic hydrocarbons in presence of aluminosilicates communication 2

Autor: Al. A. Petrov
Rok vydání: 1954
Předmět:
Zdroj: Bulletin of the Academy of Sciences of the USSR Division of Chemical Science. 3:101-107
ISSN: 1573-9171
0568-5230
DOI: 10.1007/bf01195430
Popis: 1. In presence of an aluminosilicate catalyst at 250°, acyclic and cyclic olefin hydrocarbons undergo considerable structural changes, which are readily explained by means of a mechanism scheme in which the intermediate formation of cyclopropane derivatives is postulated. The following are the most characteristic types of isomeric transformations:1) isomerization of normal olefins Into monoalkylalkenes in which the alkyl group stands at the double bond; 2) formation of dialkylalkenes from monoalkylalkenes in which the alkyl side group is well removed from the double bond; 3) breakdown of a grouping at a quaternary carbon atom, except in those cases in which, in addition to a quaternary carbon, there is a tertiary carbon at the double bond; 4) in the isomerization of CT (and higher) cycloalkenes, a mixture of two parts of six-membered and one part of five -membered naphthenes informed; 5) in hydrocarbons having a primary-secondary double bond; migration of the double bend so as to form unsymmetrically substituted ethylene derivatives readily occurs; 6) reduction in the number of carbon atoms in alkyl side groups occurs. 2. The overall result of the catalytic transformations of olefinic hydrocarbons in presence of aluminosilicate should be regarded as the summative effect of isomerization and hydrogen-redistribution processes, and the unsaturated hydrocarbons that are mainly formed are those which have the least tendency to undergo isomerization under the experimental conditions and which are readily saturated at a later stage owing to the redistribution of hydrogen. The most characteristic forms of saturated C2-C2 hydrocarbons obtained at 250° we consider to be: 2-methylalkanes; 2,3-, 2,4-, and 2,5-dimethylalkanes; methylcyclopentane; methylcyclohexane; and also 1,3-dimethylcyeiopentane and 1,4-dimethylcyclohexane.
Databáze: OpenAIRE
Externí odkaz: