Establishment Of Silanol And Polyethylene Glycol Catalysis System And Study On Their Oxidation Catalytic Properties

The thesis consists of the following four chapters:Chapterâ… : ReviewsIt reviewed the catalytic oxidation of alcohols with both metal catalysts and metal-free catalysts in this chapter. For the metal-catalyzed oxidation, the research progress were reviewed, such as: ruthenium, iron, manganese, bimetallic catalyst and other transition metal catalyst system (palladium, gold, vanadium and copper). In the second section, the applications of TEMPO and its derivatives as well as other no-metal-catalyst system (such as iodine) in the catalytic oxidation of alcohols were well discussed. And also, the new concept of"carbocatalyst"was introduced.Chapterâ…¡: Oxidation of alcohols catalyzed by dichlorodimethylsilane with hydrogen peroxideUsing hydrogen peroxide (30 %) as sole oxidant, organosilicon dichlorodimethylsilane was applied to the transformation of benzyl alcohol to benzaldehyde. The results showed that it was excellent catalyst for the oxidation of alcohols. A series of benzyl alcohols and benzhydrol derivatives were oxidized to the corresponding aldehydes and ketones with high coversion and selectivity using 30 % H₂O₂ as oxidant. On the base of that, the reactivity of substituted aromatic compounds in the oxidation of alcohols catalyzed by dichlorodimethylsilane was clarified and Hammett plot was designed in this oxidation system. Meanwhile, the mechanism of the reaction was postulated.Chapterâ…¢: Oxidation of alcohols catalyzed by dimethylsilanediol and Polyethylene glycolIn the solvent of dimethylsilanediol, for the oxidation of alcohols, dimethylsilanediol displayed good catalytic behivior. We studied the oxidation of alkyne as well as the oxidation of alcohols, and it was found that cyclodimerization for alkynes was occurred. On the base of the result, two deuterium substituted reagents were synthesized. Also the possible mechanism was postulated.Using PEG-600 as solvent and catalyst, at 120℃, oxidation transformation of alcohols to the corresponding aldehydes and ketones in the presence of air was studied. The results show that PEG-600 is good catalyst for the oxidation of alcohols. Oxidation of (18)^O enriched benzyl alcohol transformed to (16)^O benzaldehyde which shows that (16)^O come from the air oxygen. Also we postulated the mechanism of the reaction from different point of view.