The increase of noble-metal-free catalysis in organic chemistry is a trending topic in constant growth due to the price increase of noble metals and their scarce abundance. As a result, many earth-abundant transition-metal complexes containing nickel, iron, or cobalt have been successfully applied in the homogeneous catalysis of a wide number of cross-coupling reactions, and the use of pincer complexes based on these earth-abundant metals was recently explored, affording interesting results. Thus, this review provides a general overview of earth-abundant 3D pincer complexes and their application during the last decade as catalysts in cross-coupling reactions such as Kumada–Corriu, Suzuki–Miyaura, Sonogashira, C–S cross-coupling, and C–N bond-forming reactions.

The successful use of cisplatin and its derivatives clearly exemplifies the important role of metal-based compounds in cancer therapy. This review illustrates the antitumor properties of cyclometalated compounds of metals from groups 8, 9, and 10.

C–H bond activation is a crucial synthetic strategy widely utilized in both academic and industrial settings. Due to the strong and kinetically inert nature of the C–H bond, its functionalization typically requires metal-based catalysts. This review highlights the most significant advancements in homogeneously catalyzed reactions using pincer complexes with metals from groups 8–10, capable of promoting challenging C–H activation, published since 2010. In particular, it focuses on C–H bond activation for borylation, isomerization, and dehydrogenation, among other processes, discussing their scope and mechanistic insights.

The application of organometallic materials as anodes in fuel cell devices has experienced a notable increase in recent years. However, the use of POCOP pincer complexes remains scarcely explored despite their great relevance in catalysis. Thus, in this work, the electrocatalytic activity to methanol in alkaline media of three Ni(II)-based POCOP pincer complexes—[NiCl{C₆H₂-4-OH-2,6-(OPiPr₂)₂}] (a1), [NiCl{C₆H₂-4-OH-2,6-(OPtBu₂)₂}] (a2), and [NiCl{C₆H₂-4-OH-2,6-(OPPh₂)₂}] (a3)—will be discussed. The complexes were use as modifiers of carbon paste electrodes that were evaluated using cyclic voltammetry considering diverse factors, such as the absence and presence of MeOH, diverse proportions (% w/w) of the complex in the electrode, scan rate, and different MeOH concentrations. Results indicated the presence of a redox pair Ni(II)/Ni(III) with a quasi-reversible behavior in all complexes, the anodic peak currents of which were proportional to the increase in MeOH concentrations (0.05–0.3 mM), and their oxidation potentials varied in the function of the P-substituent in the Ni(II)-POCOPs backbone. Complex a1 exhibited the best current density (429.5 mA cm² at 0.5 mM) compared to its analogs a2 and a3. The current intensity of all electrodes displays good stability, which remains—with slight changes—up to 100 s. Moreover, a comparison of their catalytic rate constants suggested a great activity in complex a1 (0.52 × 10⁶ cm³ mol⁻¹ s⁻¹) compared to its analogues, implying a great activity in the electro-oxidation of MeOH. Hence, this work opens new opportunities for the electrochemical application of POCOPs complexes for future DMFCs development.

Three new POCOP-Ni( ii ) pincer complexes including methylphthalimide were obtained & their cytotoxic activity explored on six cancer cell lines. Ethidium bromide displacement & molecular docking studies showed these complexes to intercalate with DNA.