About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Paper
Kinetics of the Thermal Isomerization of Cyclopropene and 1-Methylcyclopropene
Abstract
The thermal isomerization of cyclopropene in the vapor phase in the temperature range from 472 to 502 °K led to 1-propyne as the only product. At pressures of cyclopropene of 1-3 Torr, and in the presence of an inert gas (carbon dioxide) pressure of 50-60 Torr, the kinetics of the decomposition was homogenous and obeyed the first-order rate equation up to 88% conversion. From the temperature dependence of the reaction at total pressures of ∼60 Torr, the first-order rate constant was observed to fit the equation: k = 1012.13 e-35200 ± 1300/RT sec-1. In the absence of a considerable excess of diluent gas, the reaction was not “clean”: the kinetics did not follow the first-order rate equation and the rate was greatly influenced by an increase in surface. The thermal decomposition of 1-methylcyclopropene was also studied at reactant pressures of 1-3 Torr and inert gas (carbon dioxide) pressures of 50-60 Torr. In the temperature range from 474 to 499 °K the kinetics of the over-all reaction fitted a first-order rate equation, the rate constant being given by the expression: k = l011.4e-34700±1200/RT sec-1. The products that were observed were (in the order of decreasing importance) 2-butyne, 1,3-butadiene, and 1,2-butadiene. © 1969, American Chemical Society. All rights reserved.