CPS微球固载的TEMPO的制备及其对分子氧氧化醇的催化性能

以交联聚苯乙烯(CPS)微球为载体，通过Friedel-Crafts酰基化反应和亲核取代反应化学固载2,2,6,6-四甲基哌啶氮氧自由基(TEMPO)，制备了非均相催化剂微球TEMPO/CPS，对其化学结构和形貌进行了表征；考察了主要因素对氯丁酰氯(CBC)与CPS微球Friedel-Crafts酰基化反应的影响，优化了反应条件；将微球与Fe(NO3)3构成共催化剂，用于肉桂醇和1-苯乙醇的分子氧催化氧化. 结果表明，CBC与CPS微球的Friedel-Crafts酰基化反应最适宜的Lewis酸催化剂为AlCl3，最适宜的溶剂为氯仿，反应过程中发生附加交联反应，影响微球强度，适宜的反应温度为75℃，时间为5 h，该条件下制备了TEMPO固载量为1.78 mmol/g的TEMPO/CPS微球. 其与助催化剂Fe(NO3)3构成的共催化剂具有高催化活性，可在75℃、常压氧气条件下反应24 h将1-苯乙醇氧化为苯乙酮，1-苯乙醇转化率为88%，也能有效将肉桂醇氧化为肉桂醛.

Preparation of TEMPO Immobilized on CPS Microspheres and Its Catalytic Oxidation Activity in Oxidation of Alcohols by Molecular Oxygen

The immobilization of 2,2,6,6-tetramethyl piperidine nitroxide (TEMPO) on cross-linked polystyrene (CPS) microspheres was realized via Friedel-Crafts acylation reaction and nucleophilic substitution reaction, and the heterogeneous catalyst microspheres TEMPO/CPS were obtained successfully. The chemical structure and morphology of TEMPO/CPS microspheres were characterized. The effects of different factors on the Friedel-Crafts acylation reaction between chlorobutyryl chloride (CBC) and CPS microspheres were examined, and the reaction conditions were optimized. Finally, a co-catalyst system was constructed by TEMPO/CPS and Fe(NO3)3, which was used in the oxidation reaction processes of cinnamyl alcohol as a primary alcohol and 1-phenethyl alcohol as a secondary alcohol with molecular oxygen as oxidant, respectively. The results show that for the Friedel-Crafts acylation reaction between CBC and CPS microspheres, the optimum Lewis acid catalyst is AlCl3, and the suitable solvent chloroform. During the reaction process, the additional cross-linking reaction occurs, which will weaken the strength of the microspheres. The Friedel-Crafts acylation reaction should be carried out at 75℃ and the reaction time should be 5 h. The co-catalyst system of TEMPO/CPS and Fe(NO3)3 possesses high catalytic activity, and under the conditions of lower temperature and ordinary pressure of oxygen, it can make 1-phenethyl alcohol highly effectively transform into acetophenone (1-phenethyl alcohol conversion rate of 88% at 75℃ for 24 h) and cinnamyl alcohol into cinnamic aldehyde.