Synthesis, crystal structure, theoretical calculations and antimicrobial properties of [Pt(tetramethylthiourea)4] [Pt(CN)4]·4H2O

Abstract A new platinum(II) complex, [Pt(Tmtu) 4 ][Pt(CN) 4 ]·4H 2 O ( 1 ) was synthesized by reaction of K 2 [PtCl 4 ], KCN and tetramethylthiourea (Tmtu). Its structure was determined by X-ray crystallography. The [Pt(CN) 4 ] 2− anion shows regular square planar geometry at platinum, while in the [Pt(Tmtu) 4 ] 2+ cation the geometry at platinum is somewhat distorted. Hydrogen bonding between water molecules and the cyanide nitrogen of [Pt(CN) 4 ] 2− ions stabilizes the structure and leads to a supramolecular 2D network. DFT calculations support the experimentally found dinuclear (homocoordinated) ion-pair structure 1 as the most stable in comparison to noncovalent dimer [Pt(CN) 2 (Tmtu) 2 ] 2 2 2 that could, in turn, be involved in the formation sequence of 1 . Antimicrobial activities of the complex were evaluated by minimum inhibitory concentration and the results showed that the complex exhibited moderate activities against gram-negative bacteria ( Escherichia coli , Pseudomonas aeruginosa ) and molds ( Aspergillus niger , Penicillium citrinum ).