Anatoli Onopchenko

Rhodium(I)-catalyzed hydrosilylation of styrene

La nature des produits depend du rapport rhodium/silane; et dans des conditions de reaction appropriees, les trans-styrenes β-silyles se forment de facon majoritaire

Vinyl ether end-groups in poly(ethylene glycol)s from the Na2CO3-promoted degradation of 1,3-dioxolan-2-one polymers

The Na 2 CO 3 -promoted polymerization of 1,3-dioxolan-2-one (I) to afford poly(ethylene glycol) III was reinvestigated. The reaction appeared to involve a nucleophilic attack against the carbonyl and methylene groups of I to afford poly(carbonate) II with poly(ethylene glycol) linkages and ethylene oxide IV as a side product (10-22%). As the reaction progressed, poly(carbonate) II decreased and poly(ethylene glycol) III increased. Under some conditions, poly(ethylene glycol)s V and VI with vinyl ether terminal groups were formed unexpectedly. The formation of unsaturated products during the polymerization of I/EO (ethylene oxide) has not been reported in the literature. We believe that vinyl ethers were formed from the degradation of poly(carbonate)s and were accompanied by a reduction in molecular weight. The structures of vinyl ethers V and VI were confirmed by hydrogenation of the double bond into the ethyl ether group in VII and VIII, respectively.

Nonclassical oxidation of cymenes

Cobalt(III) ion-catalysed co-oxidation of p-cymene and butane affords predominantly p-isopropylbenzoic acid, contrary to the prediction based on the classical free-radical mechanism.