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Binuclear silver(I) and copper(I) complexes, 1 and 5 , with bridging diphenylphosphine ligands were prepared. In 1 , the silver(I) center is located inside a trigonal plane composed of three phosphorus donors from three separate and bridging dppm ligands. The fourth coordination site is filled with neighboring silver(I) ions. The short Ag···Ag distance, as a result of small bite angles from bridging dppm ligands, was determined to be 2.9463(4) Å. In 5 , the Cu···Cu distance is 2.915(6) Å, significantly shorter than that observed in comparable structures. Intramolecular hydrogen bonding interactions in these complexes, such as C-H···F, C-H···O, and O-H···F interactions and π···π interactions, played a significant role in the crystal packing and stability of these molecules in the solid state. Derivatization of 1 and 5 using selected sulfur donor dialkyldithiophosphates gave six novel heteroleptic binuclear complexes. Single crystal X-ray diffraction studies of five of these complexes revealed interesting structural features, including strong metallophilic interactions in 1 and 5 and multiple intramolecular and intermolecular hydrogen bonding interactions. The antibacterial activities of complexes 1 , 2 , 3 , 7 , and 8 were also screened against gram-positive ( Staphylococcus aureus PTCC 1112) and gram-negative ( Escherichia coli PTCC 1330) bacteria. Antityrosinase and hemolytic effects of the selected compounds were also determined. Time-dependent density functional theory (TD-DFT), interaction region indicator (IRI), and fuzzy atom bond order (FBO) analyses of the selected complexes provided insights into the electronic and structural characteristics of the metal complexes.

To develop stable and efficient silver(I) catalysts and evaluate the role of sulfur and phosphorus donor ligands in the catalytic cycloaddition of selected organic azides and alkynes (AAC), a series of mononuclear Ag(I) and heteronuclear Ag(I)-Fe(II) complexes were synthesized. The synthesis utilized phosphine and sulfur donors from the dialkyldithiophosphate and borate families, specifically Na[S 2 H2B(mt) 2 ]. These complexes are designated as [(dppf)AgSP(S)(O i Pr) 2 ] (1), [S 2 H 2 B(mt) 2 Ag(μ-dppf)AgS 2 H 2 B(mt) 2 ] (2), [(dppf)Ag(μ-dppf)Ag(dppf)] (3), and [(dppe)AgS 2 H 2 B(mt) 2 ] (5). The complexes 1-5 were characterized using a combination of 1 H, 13 C{ 1 H}, and 31 P{ 1 H} NMR spectroscopy, as well as IR spectroscopy techniques. In two instances, single-crystal X-ray diffraction analysis was also employed. Complex 3 exhibited high catalytic activity and regioselectivity in the cycloaddition reaction conducted in water at 40 °C.

A novel and convenient method for the N -formylation reaction of amines with DMF as a formylating agent has been developed, utilizing a catalytic amount of diethyl phosphite/imidazole. Diethyl phosphite, as a nucleophilic catalyst, plays a significant role in this conversion. The presented method has a broad substrate scope, and various N -formyl products were obtained in good to excellent yields. Moreover, by using DMA instead of DMF, the N -acetylation reaction was also successful. The reaction of o -phenylenediamines with DMF afforded the corresponding benzimidazoles. Furthermore, N -sulfonyl amidines were obtained in good to excellent yields by the reaction of sulfonamides with DMF under similar conditions.