Tanev P T, Chibwe M, Pinnavaia T J
Department of Chemistry, Michigan State University, East Lansing 48824.
Nature. 1994 Mar 24;368(6469):321-3. doi: 10.1038/368321a0.
Titanium silicalite is an effective molecular-sieve catalyst for the selective oxidation of alkanes, the hydroxylation of phenol and the epoxidation of alkenes in the presence of H2O2 (refs 1-3). The range of organic compounds that can be oxidized is greatly limited, however, by the relatively small pore size (about 0.6 nm) of the host framework. Large-pore (mesoporous) silica-based molecular sieves have been prepared recently by Kresge et al. and Kuroda et al.; the former used a templating approach in which the formation of an inorganic mesoporous structure is assisted by self-organization of surfactants, and the latter involved topochemical rearrangement of a layered silica precursor. Here we describe the use of the templating approach to synthesize mesoporous silica-based molecular sieves partly substituted with titanium--large-pore analogues of titanium silicalite. We find that these materials show selective catalytic activity towards the oxidation of 2,6-di-tert-butyl phenol to the corresponding quinone and the conversion of benzene to phenol.
钛硅沸石是一种有效的分子筛催化剂，可用于在过氧化氢存在下对烷烃进行选择性氧化、苯酚的羟基化以及烯烃的环氧化反应（参考文献1 - 3）。然而，由于主体骨架的孔径相对较小（约0.6纳米），可被氧化的有机化合物范围受到很大限制。最近，Kresge等人和Kuroda等人制备了大孔（介孔）二氧化硅基分子筛；前者采用模板法，其中表面活性剂的自组装辅助形成无机介孔结构，后者涉及层状二氧化硅前体的拓扑化学重排。在此，我们描述了使用模板法合成部分被钛取代的介孔二氧化硅基分子筛——钛硅沸石的大孔类似物。我们发现这些材料对将2,6 - 二叔丁基苯酚氧化为相应的醌以及将苯转化为苯酚显示出选择性催化活性。
