| Description |
In the present invention, there is provided a catalytic system and use thereof for oxidation of pyridine and methyl-derivatives thereof to corresponding pyridine-1-oxides by hydrogen peroxide, containing an active catalyzing component being represented by mixed heterooxo polyanions of the general formula [(P)ia(Si)ib(B)ic(W)ip(Mo)iq(V)irOi40]ex-, wherein phosphorus is in the oxidation state +5, silicon is in the oxidation state +4, boron is in the oxidation state +3, indices a, b, c are numbers in the range of 0 to 1, wherein the sum of a+b+c=1, tungsten is in the oxidation state +6, molybdenum is in the oxidation state +6, vanadium is in the oxidation state +5, the indices p, q, r are numbers in the range of 0 through 12, wherein the sum p+r+q=12, a x=80-5a-4b-3c-6p-6q-5r, and the mixtures of these hetero polyanions, wherein the active catalyzing component is ion-immobilized on an organic anion-exchange resin. The organic anion-exchange resin is preferably represented by copolymer of divinylbenzene, being preferably selected from the group consisting of a crosslinked methyl styrene-divinylbenzene, crosslinked copolymer acrylate-divinylbenzene, and crosslinked copolymer methacrylate-divinylbenzene. The active catalytic component is immobilized through the mediation of protonized or quaternized oligoamines -[NRCHi2CHi2(CHi2)im]inNRi3e+, wherein m = 0 to 2, n = 1 to 5, and the substituent R is selected from the group consisting of hydrogen and alkyl containing 1 to 4 carbon atoms, and/or through the mediation of quaternary ammonium groups -(NR´i3)e+, wherein R´ is selected from the group consisting of alkyl containing 1 to 4 carbon atoms and 2-hydroxyethyl, bound to the organic anion-exchange resin through the mediation of methylene-CHi2- or carbonyl -(C=O)- functional group. The invention also relates to a process for preparing the above-described catalytic system.
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