ISSN:
0538-8066
Keywords:
Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The pyrolysis of 2-dimethylaminoethyl chloride in the temperature range of 360-400°C and the pressure range of 60-271 mmHg is a homogeneous, unimolecular, first-order reaction giving dimethylvinyl amine and hydrogen chloride. 2-Methoxyethyl chloride pyrolysis in the temperature range of 450-490°C and the pressure range of 53-110 mmHg by a similar unimolecular, first-order reaction yields methylvinyl ether and hydrogen chloride. These reactions were carried out in a seasoned reaction vessel and in the presence of a propene inhibitor. The methylvinyl ether decomposes slowly into other products at the temperature of pyrolysis. The rate constants are given by the Arrhenius equations(a) 2-dimethylaminoethyl chloride: \documentclass{article}\pagestyle{empty}\begin{document}$$ \log k(\sec ^{ - 1}) = (13.22 \pm 0.17) - (203.7 \pm 2.1)kJ/mol/2.303RT $$\end{document}(b) 2-methoxyethyl chloride: \documentclass{article}\pagestyle{empty}\begin{document}$$ \log k(\sec ^{ - 1}) = (14.06 \pm 0.53) - (244.7 \pm 7.1)kJ/mol/2.303RT $$\end{document}The effects of polar β substituents in the 2 position of ethyl chloride are discussed in terms of anchimeric assistance and electron-withdrawing deactivation in these elimination reactions. The present results are consistent with the heterolytic nature of the four-centered cyclic transition state for the gas-phase pyrolysis of alkyl halides.
Additional Material:
4 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/kin.550110202
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