The catalyst H3+xPMo12−x+6Mox+5O40 supported on SiO2 was developed for peroxidation of 1,3‐ and 1,5‐diketones with hydrogen peroxide with the formation of bridged 1,2,4,5‐tetraoxanes and bridged 1,2,4‐trioxolanes (ozonides) with high yield based on isolated products (up to 86 and 90 %, respectively) under heterogeneous conditions. Synthesis of peroxides under heterogeneous conditions is a rare process and represents a challenge for this field of chemistry, because peroxides tend to decompose on the surface of a catalyst . A new class of antifungal agents for crop protection, that is, cyclic peroxides: bridged 1,2,4,5‐tetraoxanes and bridged ozonides, was discovered. Some ozonides and tetraoxanes exhibit a very high antifungal activity and are superior to commercial fungicides, such as Triadimefon and Kresoxim‐methyl. It is important to note that none of the fungicides used in agricultural chemistry contains a peroxide fragment.

Stereoelectronic interactions control reactivity of peroxycarbenium cations, the key intermediates in (per)oxidation chemistry.C omputational analysis suggests that alcohol involvement as at hird component in the carbonyl/peroxide reactions remained invisible due to the absence of sufficiently deep kinetic traps neededt op reventt he escapeo f mixed alcohol/peroxidep roducts to the more stable bisperoxides.S ynthesis of b-alkoxy-b-peroxylactones, an ew type of organic peroxides, was accomplished by interrupting a thermodynamically driven peroxidation cascade. The higher energy b-alkoxy-b-peroxylactones do not transform into the more stable bisperoxides due to the stereoelectronically imposedi nstability of ac yclic peroxycarbenium intermediate as aconsequence of amplified inversea lpha-effect. The practical consequence of this fundamentalf inding is the first three-component cyclization/condensation of b-ketoesters, H 2 O 2 ,a nd alcohols that provides b-alkoxy-b-peroxylactones in 15-80 %yields.[a] Dr.

Surface peroxide species are key intermediates of photocatalytic oxidation at the TiO2 adsorbed water–gas interface.

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