ISSN:
0538-8066
Schlagwort(e):
Chemistry
;
Physical Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Cyclopropyl cyanide isomerizes in the gas phase at 660°-760°K and 2-89 torr to give mainly cis- and trans-crotonitrile and allyl cyanide, with traces of methacrylonitrile. The reactions are first order, homogeneous, and unaffected by the presence of radical-chain inhibitors. The rate constants are given by Overall: \documentclass{article}\pagestyle{empty}\begin{document}$$\log _{10} k/{\rm sec}^{ - 1} = (14.58 \pm 0.08) - (242.0 \pm 1.2){\rm kJ}\,{\rm mole}^{ - 1} /2.303RT$$\end{document} cis-Crotonitrile: \documentclass{article}\pagestyle{empty}\begin{document}$$\log _{10} k/{\rm sec}^{ - 1} = (14.01 \pm 0.11) - (237.6 \pm 1.4){\rm kJ}\,{\rm mole}^{ - 1} /2.303RT$$\end{document} trans-Crotonitrile: \documentclass{article}\pagestyle{empty}\begin{document}$$\log _{10} k/{\rm sec}^{ - 1} = (14.09 \pm 0.07) - (243.7 \pm 0.9){\rm kJ}\,{\rm mole}^{ - 1} /2.303RT$$\end{document} Allyl cyanide: \documentclass{article}\pagestyle{empty}\begin{document}$$\log _{10} k/{\rm sec}^{ - 1} = (14.59 \pm 0.13) - (252.0 \pm 1.8){\rm kJ}\,{\rm mole}^{ - 1} /2.303RT$$\end{document} where the error limits are standard deviations. On the basis of a biradical mechanism, it is deduced that the —CH—CN radical center is resonance stabilized by ca. 30 kJ mole-1. Approximate equilibrium data are given for interconversion of the 1- and 3-cyanopropenes.
Zusätzliches Material:
5 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/kin.550050112
