Cu‐ and Ni‐Grafted Functionalized Mesoporous Silica as Active Catalyst for Olefin Oxidation. Issue 31 (6th November 2017)

• Record Type: Journal Article
• Authors: Bhattacharjee, Aradhita; Das, Trisha; Uyama, Hiroshi; Roy, Partha; Nandi, Mahasweta
• Is Part Of: ChemistrySelect. Volume 2:Issue 31(2017)
• Page Start: 10157
• Page End: 10166
• Publication Date: 2017-11-06
• Subjects: Copper -- Heterogeneous catalysis -- Nickel -- Olefin -- Oxidation; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201702183
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: Mesoporous silica has been functionalized with 3‐aminopropyl triethoxy silane (3‐APTES), followed by Schiff‐base condensation with 2‐hydroxy‐1‐naphthaldehyde. Incorporation of copper and nickel by covalent grafting onto the Schiff‐base loaded materials gives two heterogenized catalysts namely, Cu–Cat andNi‐Cat, respectively. The materials have been characterized by PXRD analyses, nitrogen sorption studies, TEM, TGA, FT‐IR, UV‐visible and solid state MAS‐NMR spectroscopy. The metal‐contents in the samples are estimated using ICP‐AES studies.Cu–Cat andNi‐Cat have been used as active catalyst in the oxidation of various olefins e. g . styrene, α ‐methyl styrene, cyclohexene, trans stilbene and cyclooctene in the presence of tert ‐butyl hydroperoxide as the oxidant in acetonitrile under mild conditions. Different products have been analyzed by gas chromatography and gas chromatography‐mass spectrometry. The results show high conversion of the substrates, moderate to good product selectivity and high TOFs of the reactions. The catalysts are recycled without deteriorating their activities and heterogeneous nature. Abstract : Heterogeneous catalysts, Cu–Cat and Ni‐Cat, have been prepared by incorporating the respective metal ions on 2‐hydroxy‐1‐naphthaldehyde containing Schiff‐base anchored on mesoporous silica. These have been characterized by a number of standard techniques such as PXRD analyses, nitrogen sorption studies, TEM, FT‐IR, UV‐visible, TGA, solid state MAS‐NMR spectroscopy and ICP‐AES. These materials have been found as active and recyclable catalyst in the oxidation of various olefins. Cyclooctene is oxidized to cyclooctene oxide as the sole product.