The gas-phase elimination kinetics of ethyl 2-furoate and ethyl 2-thiophenecarboxylate

• Published in: International journal of chemical kinetics 2009-03, Vol.41 (3), p.145-152
• Main Authors: Espitia, Liliany, Meneses, Ruby, Dominguez, Rosa M., Tosta, Maria, Herize, Armando, Lezama, Jesus, Lafont, Jennifer, Chuchani, Gabriel
• Format: Article
• Language: English
• ISSN: 0538-8066; 1097-4601
• DOI: 10.1002/kin.20382

The gas‐phase elimination kinetics of ethyl 2‐furoate and 2‐ethyl 2‐thiophenecarboxylate was carried out in a static reaction system over the temperature range of 623.15–683.15 K (350–410°C) and pressure range of 30–113 Torr. The reactions proved to be homogeneous, unimolecular, and obey a first‐order rate law. The rate coefficients are expressed by the following Arrhenius equations: ethyl 2‐furoate, log k1 (s−1) = (11.51 ± 0.17)–(185.6 ± 2.2) kJ mol−1 (2.303 RT)−1; ethyl 2‐thiophenecarboxylate, log k1 (s−1) = (11.59 ± 0.19)–(183.8 ± 2.4) kJ mol−1 (2.303 RT)−1. The elimination products are ethylene and the corresponding heteroaromatic 2‐carboxylic acid. However, as the reaction temperature increases, the intermediate heteroaromatic carboxylic acid products slowly decarboxylate to give the corresponding heteroaromatic furan and thiophene, respectively. The mechanisms of these reactions are suggested and described. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 41: 145–152, 2009