Abstract

LAFONT, Jennifer J; PAEZ, Manuel S  and  ALVIS, Armando. Kinetic Study of the Thermal Decomposition of Three Derived from the Pyran (C₅H₆O). Inf. tecnol. [online]. 2009, vol.20, n.5, pp.39-46. ISSN 0718-0764.  http://dx.doi.org/10.4067/S0718-07642009000500006.

The article presents a kinetic study of the thermal decomposition of three compounds derived from pyran that have not been reported in the literature. These compounds are widely used in pharmacology to obtain important products of technological and industrial interest. The compound (2,6-dietoxitetrahydro-2H-pyran; 2-etoxi-6-propoxytetrahydro-2H-pyran and 2-etoxi-6-butoxytetra-hydro-2H-pyran) were chosen by varying the substituent located in the 6 position of the nucleus. Each experiment was done at five temperature with intervals of 10 degrees in a range between 333 and 373 K, using a microscale reaction system. The products obtained, 2-etoxy-6-hydroxy-tetrahydro-2H-pyran and ethylene, propene, or butene for each case, were identified using gas chromatography connected to masses. The reactions turned out to be unimolecular, homogeneous and of first order. Considering the kinetic and thermodynamic parameters obtained, it is possible to say that the reaction is compatible with a concerted six membered semi-polar cyclic transition state.

Keywords : thermal decomposition; kinetics; pyran; thermodynamic; reaction mechanism.

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