Functionalized carbon materials solid acids

B.iv.b. Suzuki Coupling Reactions. The cross-coupling of organoboron derivatives with carbon electrophiles, the so-called Suzuki reaction (see Sect. IIL2.2 for a review see Ref. [81]), has been conducted in various instances on a solid support. The mild reaction conditions, the compatibility with most functional groups, and the ready availability of starting material (boronic acids) have made this transformation a powerful tool in solid phase organic synthesis. 

Heterogeneous catalysts are solid materials that sometimes consist of the bulk material itself, for example, acid zeolite catalysts [10] or fused catalysts [11], Or in other cases of an active component or components deposited, as a rule, on a highly developed area support, for example, silica, alumina, carbon or in some cases a zeolite. The function of the support is to enhance the catalyst properties, for example, the stability of the active component or components, or in some cases to be even included in the catalytic reaction, for example, by providing acidic sites in bifunctional zeolite catalysts [10],... 

Another technique which is widely used for functional group analysis of humic materials is carbon-13 nuclear magnetic resonance specroscopy ( C-NMR). The C-NMR solid-state spectrum of an aquatic humic acid is shown in Figure 5. The band assignments for the types of carbon that can be detected by NMR are listed in Table III. Again, bands are broadened due to the presence of free radicals in the structure. More information can be obtained with C-NMR regarding the carbon skeleton of the humic... 

Adsorption chromatography exploits differences in the relative affinity of solutes for a solid adsorbent used as the stationary phase. Common stationary phase materials for adsorption chromatography are porous silica gel, activated alumina, activated carbon, magnesium oxide, carbonates, and highly cross-linked polymers such as styrene-divinylbenzene and methac-rylates. The chemical natures of these adsorbent stationary phase materials make them well suited for separations of solute mixtures that differ in polarity and chemical functionality. For example, silica is an acidic adsorbent that retains basic compounds to a greater extent than nonbasic ones. In contrast, alumina... 

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