Disproportionation-combination ratios of small alkyl radicals formed by the mercury-photosensitized hydrogenation of olefins in the gas phase

✍ Scribed by W. E. Falconer; W. A. Sunder

• Publisher: John Wiley and Sons
• Year: 1971
• Tongue: English
• Weight: 659 KB
• Volume: 3
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.550030606

✦ Synopsis

Disproportionation-combination ratios have been obtained for small alkyl radicals produced in the mercury-photosensitized hydrogenation of ethylene, propylene, butene-1, butene-2, and isobutene. For conditions favoring thermalized radicals, kd/k, (ethyl, ethyl) = 0.14, kd/k, (isopropyl, isopropyl) = 0.69, kd/k, (isopropyl, n-propyl) = 0.41, kd/k, (2-butyl, 2-butyl) = 0.77, kd/k, (2-buty1, n-butyl) = 0.45, and kd/k, (t-butyl, t-butyl) = 3.1. The results are consistent with kd/k, (n-propyl, n-propyl) = 0.15 and kd/k, (n-butyl, n-butyl) = 0.14. The general agreement between these disproportionationcombination ratios and those obtained where photolytic radical sources have been used

indicates that under appropriate conditions, H atom addition to olefins is a suitable source for the study of thermalized alkyl radicals and may be especially useful for larger alkyl radicals for which clean photolytic precursors are not available.