Molecular hydrogenation catalysts have been co-entrapped with the ionic liquid [Bmim]NTf(2) inside a silica matrix by a sol-gel method. These catalytic ionogels have been compared to simple catalyst-doped glasses, the parent homogeneous catalysts, commercial heterogeneous catalysts, and Rh-doped mesoporous silica. The most active ionogel has been characterised by transmission electron microscopy, X-ray photoelectron spectroscopy, and solid state NMR before and after catalysis. The ionogel catalysts were found to be remarkably active, recyclable and resistant to chemical change.

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The synthesis of [Rh2(COD)2(dppm)(μ 2 -Cl)]BF4 (1) (COD = 1,5-cyclooctadiene, dppm = bis(diphenylphosphino)methane) from simple precursors is reported. This is a rare example of a dirhodium complex with an open [Rh2(μ 2 -dppm)(μ 2 -Cl)] core. The complex has been used to affect the hydrogenation of styrene and benzo[b]thiophene with total selectivity and competitive rates of reaction. The recycling of the catalyst has been achieved by the entrapment of 1 in silica by a sol−gel method to produce a recyclable solid catalyst.

Heating 2,5-di-O-methanesulfonyl-1,4:3,6-dianhydro-D-sorbitol (1) in a range of solvents led to the formation of a gel state at low concentrations. 1 was found to gel aromatics, alcohols and water. The structure of 1 in the solid state was solved by single crystal X-ray crystallography; no strong hydrogen bonds or associated solvents were found in the crystal. Electron micrographs revealed the morphology of the gels to be predominantly rod-like. The ethanol alcogel was used to template silica by sol-gel transcription.