Synthesis, characterization, and magnetic and antibacterial properties of a novel iron( iii ) complex (CH 3 ) 2 NH 2 [Fe(phen)Cl 4 ]

A novel iron( iii ) complex (CH 3 ) 2 NH 2 [Fe(phen)Cl 4 ] (1) (phen = 1,10-phenanthroline) was synthesized, its structure was fully characterized using different techniques, and its in vitro antibacterial activity against various antibiotic-resistant Gram-positive and Gram-negative bacteria was evaluated. The structure of 1 is made up of mononuclear [Fe(phen)Cl 4 ] − anions and dimethylammonium cations (CH 3 ) 2 NH 2 + . Iron( iii ) is hexacoordinated to two nitrogen atoms of chelating phenanthroline and four chlorides forming a distorted octahedral environment around the metal atom. Complex 1 crystallizes in a triclinic system with the P 1̄ space group. 3D Hirshfeld surfaces and 2D fingerprint plots show that H⋯Cl interactions are the major contributors in maintaining the total surface. IR and UV-visible spectra indicated the coordination of 1,10-phenanthroline to iron ( iii ) metal. Thermal stability experiments revealed that 1 is stable up to 428 K. Magnetic susceptibility measurements indicated a paramagnetic behavior at high temperatures. In vitro antibacterial activity was explored against two Gram-positive bacteria, Staphylococcus aureus CECT 86 and Listeria monocytogenes CECT 4031, and two Gram-negative bacteria, Escherichia coli CECT 99 and Klebsiella pneumoniae CECT 143T, using the disc diffusion method. Complex 1 clearly showed good activity against these bacteria and is a potential candidate for treating bacterial infections and promoting further development in their treatment.