A new series of dicarboxylic derivatives of bispidines have been synthesized to develop novel copper(II) complexes suitable as imaging agents for positron emission tomography. For characterization purposes, copper complexes of bispidines were synthesized in the pure form and in quantitative yields by neutralization of ligands with malachite. The formation of complexes and their stoichiometries were studied by potentiometric titration, cyclic voltammetry, and spectroscopic methods. The stability constants were found to be fairly suitable for copper cation fixation inside dianionic chelate molecules.

Acetophenone oxime reacts with various alkenes in the presence of the rhodium catalyst [Cp*RhCl2]2 (2.5 mol%; Cp* = pentamethylcyclopentadienyl) and 1,1,1,3,3,3-hexafluoropropan-2-ol as an important cosolvent. Styrene, aliphatic terminal alkenes, and strained cyclic alkenes gave the corresponding substituted dihydroisoquinolines in yields of 50–99%. On the other hand, alkenes containing functional groups close to the double bond gave a variety of different products. The reactions of acetophenone oxime with styrene or dec-1-ene in the presence of the chiral catalyst [(C5H2 t Bu2CH2 t Bu)RhI2]2 provided the corresponding dihydroisoquinolines with improved regioselectivity but a low enantiomeric ratio (61:39 in both cases).

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There is a common assumption that replacement of the classical catalyst based on rare and expensive noble metals by the catalysts based on earthabundant metals will dramatically reduce the costs of organic synthesis. Herein we demonstrate that it may not be true, mainly because sophisticated organic substrates and modern reagents are often as expensive as catalytic amounts of noble metals. The particular cost analysis of the syntheses of 3,4-diphenyl-isoquinolone by various C−H activation methods revealed that the main costs fall on the stoichiometric reagents rather than the catalysts. As a result, the metal-free synthesis appears to be even more expensive than the procedures involving ruthenium and rhodium catalysts. Overall, metal prices should not be considered the sole reason for conducting academic research without any preliminary analysis.