Very-low-pressure pyrolysis of nitroso- and pentafluoronitrosobenzene CNO bond dissociation energies

✍ Scribed by Kwang Yul Choo; David M. Golden; Sidney W. Benson

• Publisher: John Wiley and Sons
• Year: 1975
• Tongue: English
• Weight: 440 KB
• Volume: 7
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.550070508

✦ Synopsis

The high-pressure absolute rate constants for the decomposition of nitrosobenzene and pentafluoronitrosobenzene were determined using the very-low-pressure pyrolysis (VLPP) technique.

Bond dissociation energies of DHo(C6Hs-NO) = 51.5 f 1 kcal/mole and DH" (C&s-NO) = 50.5 f 1 kcal/mole could be deduced if the radical combination rate constant is set at log k,(M-'.sec-') = 10.0 f 0.5 for both systems and the activation energy for combination is taken as 0 kcal/mole at 298'K. AH,O(CF,H~NO), AHjo(C+jF~NO), and Aff/'(C6F5') could be estimated from our kinetic data and group additivity. The values are 48.1 =t 1, -160 f 2, and -130.9 Z!Z 2 kcal/mole, respectively. C-X bond dissociation energies of several perfluorinated phenyl compounds, DHo(CsF5-X), were obtained from the reported values of AHjo(C6F&) and our estimated AHjo(C&5.