%0 Journal Article
%A W. Y. Lam, William
%A Yiu, Shek-Man
%A Yiu, Douglas T. Y.
%A Lau, Tai-Chu
%A Yip, Wing-Ping
%A Che, Chi-Ming
%D 2003
%T Kinetics and Mechanism of the Oxidation of Alkylaromatic Compounds
by a trans-Dioxoruthenium(VI) Complex
%U https://acs.figshare.com/articles/journal_contribution/Kinetics_and_Mechanism_of_the_Oxidation_of_Alkylaromatic_Compounds_by_a_i_trans_i_Dioxoruthenium_VI_Complex/3358072
%R 10.1021/ic034782j.s001
%2 https://acs.figshare.com/ndownloader/files/5197381
%K Ru
%K Other substrates
%K toluene
%K k 2
%K 21 alkylaromatic compounds
%K Alkylaromatic Compounds
%K oxidation
%K Δ H 0
%K UV
%K Marcus theory
%K fluorene
%K CH 3 CN
%K log k 2
%K benzyl alcohol
%K σ 0 values
%K rate law
%K isotope effects
%K VI
%K hydrogen atom transfer mechanism
%K oxygenated products
%K correlation
%X The oxidations of a series of 21 alkylaromatic compounds by trans-[RuVI(L)(O)2]2+ (L = 1,12-dimethyl-3,4:9,10-dibenzo-1,12-diaza-5,8-dioxacyclopentadecane) have been studied in CH3CN. Toluene is oxidized to benzaldehyde
and a small amount of benzyl alcohol. 9,10-Dihydroanthracene is oxidized to anthracene and anthraquinone. Other
substrates give oxygenated products. The kinetics of the reactions were monitored by UV−vis spectrophotometry,
and the rate law is: −d[RuVI]/dt = k2[RuVI][ArCH3]. The kinetic isotope effects for the oxidation of toluene/d8−toluene and fluorene/d10−fluorene are 15 and 10.5, respectively. A plot of ΔH⧧ versus ΔS⧧ is linear, suggesting a
common mechanism for all the substrates. In the oxidation of para-substituted toluenes, a linear correlation between
log k2 and σ0 values is observed, consistent with a benzyl radical intermediate. A linear correlation between ΔG⧧
and ΔH0 (the difference between the strength of the bond being broken and that being formed in a H-atom transfer
step) is also found, which strongly supports a hydrogen atom transfer mechanism for the oxidation of these substrates
by trans-[RuVI(L)(O)2]2+. The slope of (0.61 ± 0.06) is in reasonable agreement with the theoretical slope of 0.5
predicted by Marcus theory.
%I ACS Publications