Supported hydrogensulfate ionic liquid catalysis in Baeyer–Villiger reaction

详细信息    查看全文

• 作者：Anna Chrobok ; Stefan Baj ; Wojciech Pudł ; o ; Andrzej Jarzę ; bski
• 关键词：Immobilisation of ionic liquids ; Macroporous silica support ; Baeyer– ; Villiger oxidation
• 刊名：Applied Catalysis A: General
• 出版年：2009
• 出版时间：15 September 2009
• 年：2009
• 卷：366
• 期：1
• 页码：22-28
• 全文大小：460 K

文摘

We report here the method of synthesis and characterisation of ionic liquid: 1-methyl-3-(triethoxysilylpropyl)imidazolium hydrogensulfate, anchored onto solid support via cation–anion stays unbounded to the surface. As a support, we used a silica material with the extensive system of meso- and macropores. The structure of the support was not destroyed after the immobilisation of the ionic liquid. The new material was tested as acidic catalyst with the Baeyer–Villiger reaction. Cyclic ketones were readily oxidised with 68 % hydrogen peroxide in dry dichloromethane to their corresponding lactones in high yields (60–91 % ) at 50 °C within a short time (5–20 h). The use of hydrogen peroxide and a heterogeneous catalyst allows a clean oxidation and the possibility of easy catalyst removal by simple filtration and reuse three times in another oxidation process without lost of catalyst activity.