Supported ionic liquid-phase catalyst

Supported aqueous phase (Chapter 3, Section 3.6, Chapter 5, Section 5.2.5) and supported ionic liquid phase catalysts, Chapter 7, Section 7.3) are probably not suitable for use with higher alkenes because the liquid feed slowly dissolves some of the water or ionic liquid changing the nature of the catalyst and leading to catalyst leaching. 

SILP hydroformylation catalysts were prepared by dissolving appropriate amounts of Rh(CO)2 (acac) and ligand in dried methanol followed by stirring for 30 min. Afterwards, the ionic liquid was added to the solution. After stirring for another 30 min, the support was added and the solution stirred for 60 min. Finally, the methanol was removed in vacuo and a pale red powder was obtained. The supported ionic liquid-phase catalyst was stored imder argon for further use. 

The first fixed-bed application of a supported ionic liquid-phase catalyst was hydroformylation of propylene, with the reactants concentrated in the gas phase (265). The catalyst was a rhodium-sulfoxantphos complex in two ionic liquids on a silica support. The supported ionic liquid phase catalysts were conveniently prepared by impregnation of a silica gel with Rh(acac)(CO) and ligands in a mixture of methanol and ionic liquids, [BMIMJPFg and [BMIM][h-C8Hi70S03], under an argon atmosphere. 

An area in which functionalised ionic liquids are already playing an important role in catalysis is heterogenisation on solid supports. The general concept involves the immobilisation of imidazolium and other cationic fragments onto solid supports using appropriate functional groups attached to the cation. An ionic catalyst then resides within the ionic matrix and several examples of such supported ionic liquid phase catalysts are provided in the subsequent chapters of this book. The concept is illustrated in Figure... 

Bordoloi A, Sahoo S, Lefebvre F, Halligudi SB (2008) Heteropoly acid-based supported ionic liquid-phase catalyst for the selective oxidation of alcohols. J Catal 259 232-239... 

Table 5.6-4 Continuous, gas-phase Rh-phosphine catalyzed propene hydroformylation using silica gel-based supported ionic liquid phase catalysts containing [BMIM][PF6]1 I [91] and [92]...

Scheme 5.6-8 Pd-catalyzed Mizoroki-Heck coupling reactions between aryl halides and cyclohexyl ac7late in alkanes using silica/[BMIM][PF6] supported ionic liquid phase catalysts [105].

Ultralow Temperature Water-Gas Shift Reaction Enabled by Supported Ionic Liquid Phase Catalysts... 

I 18 Supported Ionic Liquid Phase Catalysts with Supercritical Fluid Flow... 

Haumann, M., Jakuttis, M., Franke, R., Schonweiz, A. and Wasserscheid, R, Continuous gas-phase hydroformylation of a highly diluted technical C4 feed using supported ionic liquid phase catalysts, ChemCatChem. 3,1822-1827 (2011). 

Highly polar organocatalysts such as amino acids and peptides are almost insoluble in conventional organic solvents, but they are soluble in ionic liquids. Because of these physical properties, asymmetric syntheses in ionic liquids under biphasic condition have been reported [124], Recently, combinations of solid catalysts and ionic liquids have been studied intensively. The supported ionic liquid phase catalyst is a new generation of the supported liquid-phase catalyst [125]. The supported ionic liquid phase catalyst 232 is readily prepared by adsorption of (S)-proline 13... 

Scheme 28.33 Supported ionic liquid phase catalyst 28.8...

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