两亲催化剂TS-1@Si/C催化α-蒎烯环氧化反应

Epoxidation ofα-Pinene Catalyzed by Amphiphilic Catalyst TS-1@Si/C

通过水热法制备出两亲介孔核壳材料TS-1@Si/C,采用SEM、TEM、XRD、氨气程序升温脱附等手段对其形貌和结构进行了表征。以TS-1@Si/C催化双氧水环氧化α-蒎烯合成2,3-环氧蒎烷。当n(Si)/n(Ti)为30,n(Si)/n(C)为14,催化剂的催化活性最高,反应工艺条件:α-蒎烯3 mmol,m(催化剂)/m(α-蒎烯)=7.1%,双氧水50 mmol,乙腈10 mL,水4 mL,碳酸钾2 mmol,50℃,4 h。α-蒎烯的转化率达到81.41%,2,3-环氧蒎烷的选择性为82.80%,催化剂可循环使用4次,催化活性有所下降。两亲性催化剂能形成水-油-固三相稳定界面,增大了反应底物在水相中的浓度,显著提高了催化α-蒎烯环氧化反应活性。

Amphiphilic mesoporous core-shell material TS-1@Si/C was prepared by hydrothermal method,and the morphology and structure of TS-1@Si/C were characterized by SEM,TEM,XRD and ammonia temperature programmed desorption.By using TS-1@Si/C as catalyst,2,3-epoxypinane was synthesized fromα-pinene with hydrogen peroxide as oxidant.When the n(Si)/n(Ti)molar ratio is 30 and the n(Si)/n(C)molar ratio is 14,the catalyst has the highest activity.The reaction conditions are as follows:α-pinene 3 mmol,catalyst(7.1%of the mass ratio ofα-pinene),hydrogen peroxide 50 mmol,acetonitrile 10 mL,water 4 mL,potassium carbonate 2 mmol,50℃,and 4 h.The conversion ofα-pinene was 81.41%,and the selectivity of 2,3-epoxypinane was 82.80%.The catalyst could be reused for 4 times,and the catalytic activity decreased.Amphiphilic catalyst can form stable water-oil-solid interface,increase the concentration of reaction substrate in the aqueous phase,and significantly improve the catalytic performance of epoxidation ofα-pinene.