PCC载体氧化剂的制备及应用研究

Preparation and application of supported PCC oxidants

制备得到各种有代表性的氯铬酸吡啶(PCC)无机载体氧化试剂,以苯甲醇选择性氧化成苯甲醛为探针反应,考察了载体、反应条件对氧化反应效率的影响,控制各载体氧化剂中PCC的负载量均为1.8 mmol/g。室温下反应,搅拌时间为30 m in,苯甲醇的氧化反应产率为:分子筛65.8%,活性炭75.4%,氧化铝94.6%,硅胶96.9%,相同条件下PCC的产率为65.8%。硅胶是制备负载PCC的优良载体,在载体氧化剂对苯甲醇的氧化反应中,一定范围内增加反应时间和载体加入量都可以提高氧化产率。

Some typical inorganic carriers were used to support PCC as oxidants, the activity of the supported PCC was evaluated in the selective oxidation reaction of benzyl alcohol to benzaldehyde. The effects of the kinds of carriers as well as the reaction conditions on the activity of PCC were investigated. The yield was investigated to be 65.8% （ molecular sieves）, 75.4% （ activated carbon）, 94.6% （ Al2O3 ）, and 96.9% （silica gel） when the reaction was carried out with the content of PCC of 1.8 mmol/g,and the stirring time of 30 min at room temperature. Silica gel is a good carrier for PCC. The yield can be improved with the increasing of the reaction time and the addition of the carrier in a proper range.