摘要
考察了用分子氧和不同Cu(Ⅱ)络合物对环己醇的催化氧化作用及不同强度的碱对环己醇氧化的助催化作用,找到了一个适合环烷醇氧化的催化体系:二(8-羟基喹啉)铜(Ⅱ)/t-BuONa/DMF/O_2。用此体系考察了不同摩尔比、不同溶剂、不同结构的环烷醇和不同温度对催化氧化反应的影响,并初步讨论提出的反应机理。
The oxidation of cyclohexanol catalyzed by various Cu(II) complexes with dioxygen and the influence of basic co-catalysts with different basicities on the oxidation of cyclohexanol have been studied. The more stable Cu(II) complex and the base with stronger basicity show higher catalytic and co-catalytic activities respectively.Except the stronger bases t-BuOK and t-BuOLi, the basic strength of co-catalysts corresponds with the conversion of cyclohexanol (for t-BuONa, the conversion is 23%; i-BuONa, 16%; KOH, 9%; NaOH, 3%). This is due to Cu(II) complexes can be easily decomposed and thus deactivated by the stronger base t-BuOK. The catalytic system, Cu(oxinate)2/ t-BuONa/DMF/O2, is found to be effective for the oxidation of cyclo-alkyl alcohols. In order to verify the proposed mechanism, the steric effect of substrates of different structures and the effect of bases of different basicities are also investigated
基金
国家自然科学基金
