Asymmetric Hydrogenation of Ethyl Pyruvate on Chirally Modified Pt Catalysts Supported on Periodic Mesoporous Resols
Asymmetric Hydrogenation of Ethyl Pyruvate on Chirally Modified Pt Catalysts Supported on Periodic Mesoporous Resols
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周期性介孔酚醛树脂负载的手性修饰 Pt 催化剂上丙酮酸乙酯的不对称氢化
DOI：
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发表时间：
2009
影响因子：
1
通讯作者：
Shen Ya-Li
中科院分区：
文献类型：
--
作者：
Li Xiao-Hong;Wu Peng;Wang Hong-Na;Song Li-Ying;Shen Ya-Li
以Pt（NH3）4Cl 2和H2 PtCl 6两种不同的Pt前驱体为载体，采用浸渍法制备了以FDU-14为载体的Pt催化剂。采用XRD、N2吸附、TEM和CO化学吸附等手段对Pt/FDU-14催化剂进行了表征。采用辛可尼定对Pt/FDU-14催化剂进行手性修饰后，可有效地用于丙酮酸乙酯的不对称加氢反应。以H_2PtCl_6为原料制备的Pt/FDU-14催化剂具有较高的分散度和较小的颗粒尺寸，在乙酸中的初始活性（TOF）达到21092 mol/（mol·5 h），具有较高的丙酮酸乙酯转化率。而Pt（NH3）4Cl 2衍生的Pt/FDU-14催化剂表现出更高的手性诱导能力，高达81.4%e.在乙酸中获得了（R）-（+）-乳酸乙酯的值。由于FDU-14具有很强的疏水性和纯有机骨架，Pt/FDU-14在水中也表现良好，并且可以容易地循环使用10次以上而没有明显的活性或对映选择性损失。
5.0%(Mass fraction) Pt catalysts supported on FDU-14,a kind of periodic mesoporous resols,were prepared by an impregnation method using two different Pt precursors,H2PtCl6 and Pt(NH3)4Cl2. These Pt/FDU-14 catalysts were characterized by XRD,N2-sorption,TEM and CO chemisorption. The Pt/FDU-14 catalysts can be effectively applied in the asymmetric hydrogenation of ethyl pyruvate after chirally modified with cinchonidine. The Pt/FDU-14 catalysts derived from H2PtCl6 afforded better conversions of ethyl pyruvate due to higher Pt dispersion and smaller Pt particle size,the initial activity (TOF) reaching 21092 mol/(mol5h) in acetic acid. While the Pt/FDU-14 catalysts derived from Pt(NH3)4Cl2 exhibited higher chiral induction ability and as high as 81.4% e.e. value of (R)-(+)-ethyl lactate was achieved in acetic acid. Due to the strong hydrophobicity of FDU-14 with pure organic framework,Pt/FDU-14 also worked well in water and can be recycled easily for more than 10 times without distinct loss of activity or enantioselectivity.