Abstract
A broad class of dihydroxyarenes were easily oxidized by aerobic oxygen to quinone products
in excellent yields under the catalytic effect of polymer-supported RuII-Pheox/silica-gel catalyst. By
using this combined catalyst, hydroquinone and catechol derivatives with electron-donating groups were
easily oxidized by molecular oxygen to quinone products in 90% to >99% yield, while in the case of
electron-withdrawing group, only 70% was obtained. The biologically useful 1,4-Naphthoqinone products
were obtained in 83% to 90%. The catalyst was easily obtained and reused many times without a
significant decrease in reactivity. Interestingly, a sample of industrial water contaminated with phenolic
compounds was subjected to aerobic oxidation by using this catalyst, and the resultant quinones were
detected within one day and the catalyst was removed and reused several times with different contaminating
samples with the same efficiency. Other catalytic oxidations by using this promising catalyst
were investigated.