Biomimetic Catalytic System For Selective Oxygenation Of Hydrocarbons

Hydrocarbon oxygenation for producing oxygen-containing compounds is acore technology of chemical industry. However, it continues to be a challengesince hydrocarbon is inert and its reaction is often out of control. It is of academicand applicable significance for constructing efficient biomimetic catalytic modelfrom mimicry for bio-oxidation. The studies of this thesis have been carried onthese approaches aiming at exploiting new method for selective oxygenation ofhydrocarbon under mild conditions.Based on three elementary factors of bio-oxidation: a redox center, aone-electron transfer chain, and multiple binding sites, this thesis has established ainnovative biomimetic catalytic model, composed of phthalimide-N-oxy radical,anthraquinones and zeolite HY, for selective hydrocarbon oxygenation bymolecular oxygen under mild conditions. 95.8% Selectivity of acetophenonewithout any over-oxidation products and 66.2% conversion were accomplishedfor oxygenation of ethylbenzene at temperature as low as 80oC and 0.30 MPa O₂pressure.Another biomimetic catalytic model in this thesis is composed ofN-hydroxyphthalimide and anthraquinones, typically 1,4-diamino-2,3-dichloro–anthraquinone, which exhibit excellent catalytic activities and selectivitiesduring oxygenation of different kinds of hydrocarbon and is the firstorganocatalytic system for hydrocarbon oxygenation under mild conditions in theabsence of stoichiometric reductant and radical initiator. For example, 84.5% offluorene was oxygenated to fluorenone as a sole product at 80oC. The interaction between N-hydroxyphthalimide and anthraquinone has firstlybeen observed by a liquid in situ FTIR system assembled in this thesis. Accordingto its conclusion, the radical mechanismof hydrocarbon oxygenation catalyzed bythe biomimetic catalytic model has been demonstrated, which is via one electrontransfer and resembles the enzymatic radical oxygenation. The non-radical mechanism of alkyl peroxide converting selectively toketone catalyzed by zeolite HY in the biomimetic catalytic model has been firstlyproposed, which is a synergetic decomposition of a protoned transition stateformed via two hydrogen bonds. Therefore, the catalysis of zeolite HY resulting inreaction orientation has successfully mimicked the action of protein surroundingof enzyme.