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The Pd-catalyzed selective hydrogenation of C C double bond in (3,3-diphenylallyl)diisopropylamine or 3,3-diphenylallyl alcohol was evaluated using different catalytic systems [Pd/C, Pd(OAc)2/ionic liquid, isolated Pd(0) nanoparticles]. For the (3,3-diphenylallyl)diisopropylamine, hydrogenolysis is preferred over hydrogenation, and only moderate selectivities were obtained for the desired product. However, complete conversion and 100% selectivity were obtained for the hydrogenation of 3,3-diphenylallyl alcohol using isolated Pd(0) nanoparticles under mild condition. This successful strategy enabled the effective synthesis of diisopromine and feniprane drugs and opens new possibilities for the preparation of other biologically active compounds.

The Pd-catalyzed oxidative esterification of benzaldehyde with methanol using organic halides as oxidant agents is reported. Our results demonstrate the crucial role of the ligand in the choice of the oxidant for this reaction. Phenyl bromide can be used as oxidants by using dppp as ligand. On the other hand, benzyl bromide is much more selective when PPh 3 is used as the ligand. We were able to detect the key benzyl palladium intermediate in the catalytic cycle by using ESI-MS-(+). We also performed a one-pot C Br reduction/aldehyde oxidative esterification without the need for external oxidant agents.

The reaction of glycerol with phenylboronic acid provided a mixture of cyclic glycerol esters, glycerol 1,2-phenylboronate (80%), and glycerol 1,3-phenylboronate (20%). The latter two products were formed from the esterification of the 1,2- and 1,3-hydroxyl groups, respectively. The glycerol phenylboronates were applied to the Pd-catalyzed Suzuki cross-coupling reactions with aryl halides, affording the corresponding biphenyl products in high yields. Excess glycerol phenylboronate was not required, and the Suzuki coupling reaction employed a simple catalyst precursor prepared in situ from palladium acetate and triphenylphosphine under mild reaction conditions. Arylboronic acid and pinacol arylboronic ester yielded similar results under the optimized reaction protocol.

The electrocatalytic reduction of NO 3 - (aq) over platinum has been investigated in sulfuric acid solutions with proton concentrations between 1 mM and 50 mM. Cyclic voltammetry indicates that for [H+] NO 3 - (aq) is reduced in two distinct regions of potential: one reduction peak occurs at approximately 0.1 V vs. RHE and one occurs at −0.13 V vs. RHE. This second reduction peak has never before been observed, and is not present for proton concentrations >10 mM, where hydrogen electroreduction prevails below 0.0 V vs. RHE. Chronoamperometry shows that the kinetics of the two reduction peaks are distinct, suggesting that the two reduction peaks may correspond to the evolution of different products. Results are discussed in the context of tuning the product selectivity of the electrocatalytic reduction of NO 3 - (aq).