Pd负载双金属氰化物高收率催化糠醛转化为环戊酮

Double-metal cyanide supported Pd catalysts for highly efficient cyclization of furfural to cyclopentanone

生物质衍生品糠醛转化为环戊酮是合成高附加值化学品的重要反应。但是当前,在金属/载体双功能催化剂Br⌀nsted酸的作用下,会生成大量的腐蚀质,导致炭收率较低。因此,本文合成纯Lewis酸的双金属氰化物作为载体负载Pd金属用于反应。研究发现,通过不同种类的双金属氰化物拥有不同的酸性,比表面积受到配位化合物的影响。负载后Pd以8nm的大小分散在双金属氰化物的表面。催化反应时,Pd/FeZn得到了97.2%收率的环戊酮,而Pd/FeNi,Pd/FeCo得到超过92.5%收率的糠醇。并且催化剂热稳定性和化学稳定性能良好,循环五次后没有明显活性下降。这个研究不仅仅提供了一种糠醛高收率转化为环戊酮的方法,而且研究了双金属氰化物基双功能催化剂的优势,对其他催化反应有启迪作用。

The cyclization of biomass-derived furfural to cyclopentanone compounds was great significant for the synthesis of high value chemicals. Currently,the metal/support bifunctional catalysts is confronted with serious carbon loss caused by Br?nsted acid or the difficulty of hydrolysis reaction due to the weak Lewis acidity. Herein, double-metal cyanide with pure moderate Lewis acid sites was used to solve above problems. The crystal structure and acidity are controlled by the different kinds of metals,and the surface area is also changed by complexing effect. The Pd clusters are uniformly dispersed on the surface with 8 nm after impregnation on the double-metal cyanide. For the reaction of furfural,the moderate acidity Pd/ FeZn shows the high efficiently synthesis of cyclopentanone compounds, whereas weak acidity Pd/FeNi and Pd/FeCo results in above 90. 2% yield of furfural alcohol. The activity was controlled by the surface area based on the accessibility of acid sites. Furthermore,the catalyst is resistant to leaching and performs stably after 6 runs. This study not only provides a prom ising route for the efficiently production of cyclopentanone compounds, but also shows the excellent advantage of DMC-based bifunctional catalysis in biomass reaction.