Kinetic study of 2‐furanaldehyde, 3‐furanaldehyde, and 5‐methyl‐2‐furanaldehyde reactions initiated by Cl atoms

Abstract

AbstractRate coefficients for the gas‐phase reactions of chlorine atoms with a series of furanaldehydes have been determined at 298 ± 2 K and atmospheric pressure (708.5 ± 0.1). The experiments were performed using the relative technique combined with solid‐phase microextraction (SPME) sampling and gas chromatography with flame ionization detection (GC‐FID). Rate constants were determined relative to the reaction of Cl withn‐nonane and 2‐ethylfuran. The absolute rate coefficientsk(in units of 10−10cm3molecule−1s−1) obtained were 2.61 ± 0.27 for 2‐furaldehyde, 3.15 ± 0.27 for 3‐furaldehyde, and 4 ± 0.5 for 5‐methyl‐2‐furaldehyde. This study shows that the reactions of furanaldehydes and Cl are very fast with little influence of the position of the aldehyde group or the presence of other substituent on the reactivity. The results seem to indicate a mechanism involving two main reaction channels, addition of chlorine atom to the double bond of the aromatic ring, and the abstraction of the aldehydic hydrogen. Further product studies are necessary to determine the mechanism of these reactions in more detail. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 670–678, 2008