The kinetics of the gas‐phase thermal isomerization and decomposition of Trans ‐ and Cis ‐1,2‐Bis(trifluoromethyl)‐1,2,3,3‐tetrafluorocyclopropane

The kinetics of the gas‐phase thermal isomerization between trans ‐ and cis ‐1,2‐bis(trifluoromethyl)‐1,2,3,3‐tetrafluorocyclopropane as well as their decomposition to trans ‐ and cis ‐perfluoro‐2‐butene, respectively, and CF 2 , was studied in the temperature range of 473–533°K, with an initial pressure of reactant of 1.5 to 7.0 Torr. Some runs were also made with the addition of SF 6 as an inert gas up to a total pressure of 100 Torr. The reactions are first order and homogeneous. The rate constants for the geometrical isomerization fit the following Arrhenius relations:\documentclass{article}\pagestyle{empty}\begin{document}$$ {{\log {k}_{{trans}\to {cis}}}\mathord{\left/{\vphantom {{\log {k}_{{trans}\to {cis}}}{(\sec ^{ - 1})}}}\right.\kern-\nulldelimiterspace}{(\sec ^{ - 1})}}{ = }{{{(15}{.15}\pm{0}{.16)-(44,487}\pm{ 374)}}\mathord{\left/ {\vphantom {{{(15}{.15} \pm{0}{.16) - (44,487 }\pm { 374)}}{4.576{ }T}}} \right.\kern-\nulldelimiterspace} {4.576{ }T}} $$\end{document}\documentclass{article}\pagestyle{empty}\begin{document}$$ {{\log {k}_{{trans}\to {cis}}}\mathord{\left/{\vphantom {{\log {k}_{{trans}\to {cis}}}{(\sec ^{ - 1})}}}\right.\kern-\nulldelimiterspace} {(\sec ^{ - 1})}}{ = }{{{(15}{.35} \pm {0}{.19) - (43,419 } \pm { 428)}} \mathord{\left/ {\vphantom {{{(15}{.35} \pm {0}{.19) - (43,419 } \pm { 428)}} {4.576{ }T}}} \right. \kern-\nulldelimiterspace} {4.576{ }T}} $$\end{document} and the corresponding equations for the decomposition of the trans and cis ‐cyclopropane are\documentclass{article}\pagestyle{empty}\begin{document}$$ {{\log {k}_{{trans}}} \mathord{\left/ {\vphantom {{\log {k}_{{trans}}} {(\sec ^{ - 1})}}} \right. \kern-\nulldelimiterspace} {(\sec ^{ - 1})}}{ = }{{{(15}{.14} \pm {0}{.28) - (46,700} \pm { 652)}} \mathord{\left/ {\vphantom {{{(15}{.14} \pm {0}{.28) - (46,700 } \pm { 652)}} {4.576{ }T}}} \right. \kern-\nulldelimiterspace} {4.576{ }T}} $$\end{document}\documentclass{article}\pagestyle{empty}\begin{document}$$ {{\log {k}_{{cis}}} \mathord{\left/ {\vphantom {{\log {k}_{{cis}} } {(\sec ^{ - 1})}}} \right. \kern-\nulldelimiterspace} {(\sec ^{ - 1})}}{ = }{{{(15}{.39} \pm {0}{.26) - (46,639} \pm { 598)}} \mathord{\left/ {\vphantom {{{(15}{.39} \pm {0}{.26) -(46,639 } \pm { 598)}} {4.576{ }T}}} \right. \kern-\nulldelimiterspace} {4.576{ }T}} $$\end{document} .