Reagents, hydrocarbon cores

Raman experiments, antiferroelectrics 667 randomly constrained nematics 189 Rapini-Popular terms 77 rational routes, hydrocarbon cores 705 Rayleigh interferometer 131 Rayleigh scattering 172 reagents, hydrocarbon cores 694 ff rectangular phases... 

This dendron class is a special example of a dendron series possessing radially oriented heterogeneous generations. The dendrons possess branch cells derived from three different branch cell reagents, namely an alkyltriol, triethyl methane-tricarboxylate and aminotris-(hydroxymethyl)methane. Newkome [92] refers to this series as uni-directional arborols (Scheme 5, see next page). A maximum of three branch cell layers were grown from the hydrocarbon core. 

We thus infer a great similarity in the chemistry of the pi electrons of graphite and of small aromatic hydrocarbons. Apparent divergences arise for cases in which the aromatic molecules form sigma complexes, whose creation is not easily perceptible for graphite, simply because of the low ratio of peripheral carbon to internal carbon. While many coals do contain aromatic clusters, the chemistry of their pi electrons is altered by the presence of substituents which alter the electronic and steric properties of the aromatic core. Additionally, added chemical reagents may react directly not only with these substituents but also with mineral phases present in the coal to yield a product in which the pi aromatic chemistry is masked. 

Scheme 1 and Figs. 1 and 2 illustrate the essential elements of the chemical trapping method and the assumptions required to interpret product yield results. The chemical trapping reagent is prepared as the 4-alkyl-2,6-dimeth-ylarenediazonium tetrafiuoroborate, z-ArN2Bp4, and it is the z-ArNj ion that functions as the chemical probe. Water soluble l-ArNj (z = 1, alkyl = CH3) is used for studies in aqueous solution in the absence of micelles (Fig. 2). Water-insoluble Ih-ArNj (z = 16, alkyl = C16H33) is used in micelles because its hydrocarbon chain binds the probe to the micellar core and its cationic head group orients the reactive diazonio group in the interfacial region of the micelles (Figs. 1 and 2). We use a preassociation model, Scheme 1, a modified form of the heterolytic dediazoniation mechanism proposed by...

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