Reprinted from J. Photochem. Photobiol. A: Chem., 110, 243-246 (1997).
© Elsevier, 1997.
Corinna Kerst, Rabah Boukherroub, and William J. Leigh*
Contribution from the Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1
Abstract: Far-UV (193-nm) laser flash photolysis of nitrogen-saturated isooctane solutions of 1,1-dimethylsiletane allows the direct detection of 1,1-dimethylsilene, as a transient species which (at low laser intensities) decays with pseudo-first order kinetics (t ~ 10-µs) and exhibits a UV absorption spectrum with lmax ~ 255-nm. Characteristically rapid quenching is observed for the silene with methanol (kMeOH = (4.9 ± 0.2) x 109 M-1s-1), tert-butanol (kBuOH = (1.8 ± 0.1) x 109 M-1s-1), and oxygen (kO2 = (2.0 ± 0.5) x 108 M-1s-1). Arrhenius activation parameters for the reaction with methanol have been determined to be Ea = -2.6 ± 0.6 kcal/mol and log A = 7.7 ± 0.3.