ISSN:
0538-8066
Keywords:
Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The photolysis of 2-methylcyclohexanone has been studied in the gas phase at 313 nm, mainly at 100°C, over a range of pressures. The Hg(63P1) photosensitized decomposition has also been investigated at 100°C. Under conditions of high excitation and/or little collisional quenching the major products are carbon monoxide and the hydrocarbons: 1-hexene, trans-and cis-2-hexene and methylcyclopentane, with minor aldehyde formation. The various product ratios are presented in tabular form. At lower excitation energies, and with increased collisional deactivation, trans- and cis-5-heptenal become important products, and the trans/cis aldehyde ratio is seen to be slightly pressure dependent when all the systems are compared. Similarly, there is a small pressure dependence for the Σ hexenes/methylcyclopentane ratio. From experiments at 250°C the temperature dependence of this ratio was established, and for thermalized hexane-1,5-diyl an activation energy difference (Ed - Ec) = -1.3 kcal mol-1 has been determined for the disproportionation and combination of the biradical. The mechanism for the photolysis is discussed in terms of triplet state photochemistry and biradical intermediates as developed, in particular, by Frey and coworkers, this Journal, 16, 1337 (1984).
Additional Material:
3 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/kin.550200502
