二氧化硅负载的聚-γ-氨丙基硅氧烷金属络合物对苯胺氧化乙氧羰墓化生成苯基氨甲酸乙酯反应的催化作用

Oxidative Ethoxycarbonylation of Aniline to Ethyl Phenylcarbamate Catalyzed by Silica-supported Poly-γ-Aminopropylsiloxane-Metal Complexes

合成了二氧化硅负载的聚-γ-氨两基硅氧烷(简称:SiO_2>Si-NH_2)的单金属及双金属络合物(分别简称:SiO_2>Si-NH_2-M,M=C_O或 Cu;SiO>Si-NH_2-Cu-M′,M′=Co,Sn,Mn,Ni或Fe),考察了这些高分子金属络合物对苯胺氧化乙氧羰基化生成苯基氯甲酸乙酯反应的催化作用。结果表明,铜一钻双金属络合物(SiO_2>Si-NH_2-Cu-Co)的催化活性和选择性高于其他几种金属络合物,在温和的反应条件下可使苯胺以90％以上的转化率和大于80％的选择性转化成苯基氨甲酸乙酯。考察了各种反应条件对SiO_2>Si-NH_2-Cu-Co催化性能的影响,用测定转化数的方法研究了其稳定性。 SiO_2>Si-NH_2-Cu,SiO_2>Si-NH_2-Co和SiO_2>Si-NH_2-Cu-Co的XPS及IR研究结果表明,在高分子金属络合物中,氮与金属之间形成了配位键,每种金属都存在一种以上的结构形态。双金属络合物中两种金属存在相互作用。

Several silica--supported poly--γ--aminopropylsiloxane--monometal or bimetalcomplexes (SiO_2) Si--NH_2-M, M=Cu or Co; SiO_2>Si-NH_2-Cu-M′,M′= Co,Sn, Mn, Ni or Fe) were prepared. Their catalytic properties for oxidativeethoxycarbonylation of aniline to ethyl phenylcarbamate have been investigated. The catalytic reaction was carried out under relatively mild conditions. The catalyst SiO_2>Si--NH_2--Cu--Co has the highest yield of ethyl phenylarbamate in these catalysts, andthe conversion of aniline could amounted to over 90% with 80% selsectivity and 450turnover numbers (molar of aniline converted/molar of metal in SiO_2> Si-NH_2--Cu--Co added) under conditions: 150℃, 4 MPa (CO/O2=3), 40 hours. The results of XPS and IR indicated that the coordination bonds were formedbetween nitrogen and metal in SiO_2>Si-NH_2-Cu, SiO_2>Si-NH_2-Co and SiO_2>Si-NH_2-Cu-Co. There are more than one structure states for and metalsin catalysts. In SiO_2>Si-NH_2-Cu-Co, there was interaction between Cu and Co.