One of the most active areas within the field of bioorganometallic chemistry, complexes of N-heterocyclic carbenes (NHCs), have recently gained interest. Herein, we report two luminescent palladium N-heterocyclic carbene complexes; namely [Pd {(C,N)-C 6 H 4 CH 2 NH(CH 2 CH 3 )}(1)] (2) and [Pd{(C,N)-C 6 H 4 CH 2 NH 2 }(1)] (3) (1 = 1-methyl-3-(2-oxo-2-(pyren-1-yl)ethyl)-2,3-dihydroimidazol-2-ylidene) which were synthesized from the reaction of luminescent imidazolium salt (1(H)Br) and binuclear Palladacycles. The interactions of them with CT-DNA evaluated via absorption, emission and CD spectral techniques as well as measurements of viscosity and thermal denaturation and the results have been shown that they bounded to CT-DNA by intercalation and groove binding modes. The in vitro cytotox-icity of compounds 2-3 and 1(H)Br on human breast (MCF-7) and cervical epithelial carcinoma (HeLa) cancer cells lines, indicated the wide range of anticancer activities of them with low IC 50 values. Moreover, based on the protein binding ability studies, the intrinsic fluorescence of BSA could be strongly quenched by compounds via a static quenching mechanism. Competitive binding study using Eosin, Digoxin and Ibuprofen as site markers, indicated that the compounds could bind to sites I and II on BSA structure. Finally, all data obtained from biophysical studies were validated by molecular modeling study. Computational results showed that palladium complexes have the potential for detection of mismatch DNA.

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The growing concern about the potentially adverse effects of the production of chemical compounds on the sustainable development of the environment has led to a great deal of efforts to search for low-cost and environmentally friendly catalytic systems. A pyrene-tagged N-heterocyclic carbene palladacycle complex ([Pd{(C,N)C 6 H 4 CH 2 NH(Et)}(Imd-P)Br]) was prepared by reacting imidazolium salt with dimer ([Pd 2 {(C,N)C 6 H 4 CH 2 NH(Et)} 2 (μ-OAc) 2 ]). Then, it was immobilized onto the surface of reduced graphene oxide (rGO) via π-π stacking forces. The hybrid compound ((NHC)Pd-rGO) was made in a one-step process. Various techniques were employed to characterize the compound. In addition, computational studies were used to verify the interaction between the Pd complex and rGO. The catalytic activity of the molecular complex and hybrid material was evaluated in both Suzuki-Miyaura cross-coupling reactions and reduction of p-nitrophenol to p-aminophenol. The catalytic activity of the hybrid material was enhanced in comparison with the corresponding homogeneous analogue. Thus, rGO seems to play a significant role in catalytic activity. Hot filtration experiments show the heterogeneous nature of the catalyst resulting from the strong interaction between pyrene and graphene. The hybrid (NHC)Pd-rGO material could be recycled up to six times with no decrease in catalytic activity.

In this study, the divergent and magnetic separation method is employed to prepare polyamidoamine (PAMAM) dendrons functionalized magnetic graphene oxide (MGG3) using graphene oxide supported MnFe2O4 nanoparticles as the support (MG), and ethylenediamine (EDA) and methylacrylate (MA) as the precursors of PAMAM dendron. Finally, palladium ions as active catalytic sites are immobilized on the support (MGG3‐Pd). The morphology and structure of the MGG3‐Pd nanocomposite thus produced are characterized by elemental analysis, Fourier transform infrared (FT‐IR), powder X‐ray diffraction (XRD) analysis, thermogravimetric analysis (TGA), field emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), energy dispersive X‐ray spectroscopy (EDS), inductively coupled plasma atomic emission spectroscopy (ICP‐AES), X‐ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), and Zeta potential analysis. Subsequently, the catalytic activity of the MGG3‐Pd nanocomposite is studied in the reaction of 4‐nitrophenol (4‐NP) with sodium borohydride as the reducing agent at room temperature. The MGG3‐Pd catalyst is found to exhibit an excellent catalytic activity in the reduction of 4‐NP with a high yield over a short reaction time and at a rate constant (k) of 16.82 × 10−3 s−1. Furthermore, the MGG3‐Pd catalyst thus produced can be recycled at least after 10 runs of 4‐NP reduction without any considerable loss of Pd content. The reduction of other nitroaromatic compounds is also investigated under optimal conditions to illustrate the catalyst's versatility.