Development of Biomimetic Catalytic Systems for Selective Oxidations with H2O2 and O2

Detta är en avhandling från Department of Organic Chemistry

Sammanfattning: Four different catalytic systems were studied for biomimetic coupled oxidations using H2O2 or O2. In the first example, osmium tetroxide works as a substrate-selective catalyst for dihydroxylation of olefins. Electron transfer to H2O2 is facilitated by electron transfer mediators (ETMs). In one case VO(acac)2 or MeReO3 was used as ETM; in the other case a combination of flavin and tertiary amine was used as ETMs. These three systems were immobilized in the ionic liquid [bmim]PF6 for the purpose of recycling of the catalyst.In the second example, an organocatalyst (a flavin) was used for the oxidation of sulfides to sulfoxides and this catalytic system was recycled and reused in an ionic liquid.In the third example, primary aromatic amines were oxidized by H2O2 to nitroso compounds in a selenium-catalyzed oxidation. The nitrosoarenes were used in a one-pot hetero Diels-Alder reaction with dienes forming 1,2-oxazines.In the fourth example, a cobalt salophen complex was immobilized in different zeolites. The catalyst was used in aerobic oxidation of p-hydroquinone and the zeolite catalyst could be reused. The oxidative carbocyclization of ene-allenes was tested successfully using the triple catalytic system consisting of palladium(II), p-benzoquinone, and the immobilized catalyst for O2 activation.All these systems gave mild and selective oxidations with environmentally friendly and inexpensive terminal oxidants.

  Denna avhandling är EVENTUELLT nedladdningsbar som PDF. Kolla denna länk för att se om den går att ladda ner.