CAJ | 학술논문

通过共聚法合成了嵌入式仲胺官能化的MCM-41,利用接枝法制备出介孔分子筛MCM-41负载的手性Salen Mn(Ⅲ)催化剂.采用FT-IR、DR UV-Vis、XRD、N2吸附、ICP等手段对其进行了表征.以其为催化剂,次氯酸钠、间氟过氧苯甲酸为氧化剂,分别用于苯乙烯、1,2-二氢化萘、顺-β-甲基苯乙烯以及α-甲基苯乙烯等非官能团化烯烃的不对称环氧化反应.当以间氯过氧苯甲酸为氧化剂时,催化剂显示较高的转化率、环氧化物选择性和对映体过量值,但与相应的均相催化剂比,负载后催化剂活性和对应选择性都有所降低.同时对催化剂的循环使用性能进行了考察,发现络合物在催化反应过程中分解是催化剂失活的主要原因.
통과공취법합성료감입식중알관능화적MCM-41,이용접지법제비출개공분자사MCM-41부재적수성Salen Mn(Ⅲ)최화제.채용FT-IR、DR UV-Vis、XRD、N2흡부、ICP등수단대기진행료표정.이기위최화제,차록산납、간불과양분갑산위양화제,분별용우분을희、1,2-이경화내、순-β-갑기분을희이급α-갑기분을희등비관능단화희경적불대칭배양화반응.당이간록과양분갑산위양화제시,최화제현시교고적전화솔、배양화물선택성화대영체과량치,단여상응적균상최화제비,부재후최화제활성화대응선택성도유소강저.동시대최화제적순배사용성능진행료고찰,발현락합물재최화반응과정중분해시최화제실활적주요원인.
An embedded secondary amino group modified MCM-41 was synthesized by CO-polymerization method. Then the material was used as a support to immobilize a chiral Salen Mn (Ⅲ) complex. The immobilized complex was characterized by FT-IR DR UV-Vis,XRD,N2 adsorption-desorption and ICP methods,respectively. The material Was used as a catalyst for the asymmetric epoxidation of styrene,1,2-dihydronaphthalene,cis-β-methylstyrene,and α-methylstyrene with NaCIO and m-chloroperoxybenzoic acid (m-CPBA) as oxidants,respectively. The catalyst showed higher conversion of substrate. selectivity of epoxide and enantioselectivity with m-CPBA as oxidant. However, both the activity and enantioselectivity of the complex decreased obviously after immobilization compared with those of the homogeneous one.The reusability of the catalyst was also studied and it was found that the decomposition of the complex in the catalytic runs was the main reason which led to the deactivation of the catalyst.