An ordered hydrophobic P6mm mesoporous carbon with graphitic pore walls and its application in aqueous catalysis

Abstract

A hydrophobic ordered mesoporous carbon with hexagonal arrays of rods was synthesized by a nanocasting process by using silica SBA-15 as a template and 2,3-dihydroxynaphthalene as a fused-aromatic carbon precursor. Impregnation of 2,3-dihydroxynaphthalene and its subsequent conversion into carbon occurred inside the mesopores of the silica template through a dehydration reaction between the surface silanols and hydroxyl groups of the carbon source and mild carbonization under inert atmosphere. After silica removal, X-ray scattering, transmission electron microscopy, pore size analysis and Raman spectroscopy showed that the resulting material was a negative replica of the silica template with a 2D-hexagonal P6mm ordered structure, possessing a large surface area (724 m 2 g −1), a monomodal pore size distribution (3.4 nm) and a relative hydrophobic surface with graphitic pore walls. These features give the system substantial advantages to play a beneficial role in aqueous organometallic catalysis. The material appeared to be an excellent mass transfer promoter to enhance the overall reaction rate of the palladium-catalyzed cleavage reaction of water-insoluble allylundecylcarbonate (Tsuji–Trost reaction).