The Suzuki coupling reaction of basic nitrogen containing substrates (2-bromo- and 2-chloro-4-aminopyridine, and 2-bromo and 2-chloropyridine) with phenylboronic acid using Pd(TPP)2Cl2/K3PO4 in acetonitrile-water biphasic solvent systems under a CO2 or a N2 atmosphere is discussed. It was observed that 2-halo-4-aminopyridine produced quantitative yields of coupled products under a CO2 atmosphere while the yields for the 2-halopyridines were poor. In contrast, the yields of coupled products for the 2-halopyridines substrates were quantitative under a N2 atmosphere while only poor yields were realized for the 2-halo-4-aminopyridines under the same conditions. Evidence is presented which suggests that the presence of CO2 alters the pH of the aqueous phase of the reaction system and the accompanying efficiency of the coupling process. Using a series of buffers to adjust the pH of the aqueous phase, the pH dependence associated with the efficiency of the coupling process is illustrated.

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A new approach for characterization of fluid catalytic cracking (FCC) catalysts is proposed. This approach is based on computational visual analyses of images originating from field emission scanning electron microscopy (FE-SEM) studies coupled with elemental mapping via electron dispersive x-ray spectroscopy (EDX) analyses. The concept of contaminant metal mobility is defined and systematically studied through quantification of interparticle transfer and intraparticle penetration of the most common FCC contaminant metals (nickel, vanadium, iron, and calcium). This novel methodology was employed for practical quantification of intraparticle mobility via the Peripheral Deposition Index (PDI). For analyzing and quantifying interparticle mobility, a new index was developed and coined “Interparticle Mobility Index” or IMI. With the development and practical application of these two indices, this study offers the first standardized methodology for quantification of metals mobility in FCC. This novel systematic approach for analyzing metals mobility allows for improved troubleshooting of refinery-specific case studies and for more effective research and development in contaminant metals passivation in FCC catalysts.