在氯甲基化交联聚苯乙烯微球表面合成与固载手性金属-Salen配合物及其表征

氯甲基化交联聚苯乙烯(CMCPS)微球的氯甲基与苯甲醛衍生物2-羟基-3-甲氧基苯甲醛(HMBA)发生傅克烷基化反应,形成改性微球HMBA-CPS;微球HMBA-CPS与环己二胺发生席夫碱反应,形成键合Salen配基的微球Salen-CPS;最后，使之与锰盐发生配位螯合反应,制得了固载有手性Mn(Ⅲ)-Salen配合物的固体催化剂Mn(Ⅲ)Salen-CPS，分别采用红外光谱、紫外/可见吸收光谱及扫描电子显微镜对固体催化剂的结构与形貌进行了表征和观察。 研究了微球CMCPS与HMBA之间傅克烷基化反应的规律。 结果表明,以AlCl3为Lewis酸催化剂,使用二氯甲烷与硝基苯混合溶剂,可有效地实施CMCPS与HMBA的傅克烷基化反应,制得固体催化剂Mn(Ⅲ)Salen-CPS。 在V(CH2Cl2)∶V(NB)=10∶1的混合溶剂中,40 ℃下反应10 h,可制得氯甲基转化率近于51%的改性微球HMBA-CPS。 该制备途径具有简便、高效与快捷的特点。

Synthesis, Immobilization and Characterization of Chiral Metal-Salen Complex onChloromethylated Crosslinked Polystyrene Microspheres

Firstly, the Friedel-Crafts alkylation between the chloromethylated crosslinked polystyrene(CMCPS) microspheres and 2-hydroxy-4-methoxybenzaldehyde(HMBA) was carried out to afford the modified microspheres HMBA-CPS. Subsequently, the Schiff base reaction between HMBA-CPS and diaminocyclohexane was performed, leading to the microspheres Salen-CPS, on which Salen ligands were bonded. Finally, the coordination-chelating reaction of Salen-CPS with Mn salt was conducted, resulting in solid catalyst Mn(Ⅲ)Salen-CPS, on which chiral Mn(Ⅲ)-Salen complex was immobilized. The microspheres Salen-CPS and Mn(Ⅲ)Salen-CPS were fully characterized by methods such as FTIR, UV-Vis and SEM. The Friedel-Crafts alkylation between CMCPS microspheres and HMBA was mainly investigated because it was a key reaction. The results show that the Friedel-Crafts alkylation can be carried out when AlCl3 was used as Lewis catalyst and a mixture of dichloromethane and nitrobenzene was used as solvent. The new route is simple, convenient, direct and efficient. Under the suitable reaction conditions(volume ratio of dichloromethane to nitrobenzene=10∶1, temperature=40 ℃, and reaction time=10 h), modified microspheres HMBA-CPS capable of converting chloromethyl with a 51% rate can be obtained.