TY - JOUR
T1 - Synthesis, characterization, DFT calculations and antibacterial activity of palladium(II) cyanide complexes with thioamides
AU - Ahmad, Saeed
AU - Nadeem, Shafqat
AU - Anwar, Aneela
AU - Hameed, Abdul
AU - Tirmizi, Syed Ahmed
AU - Zierkiewicz, Wiktor
AU - Abbas, Azhar
AU - Isab, Anvarhusein A.
AU - Alotaibi, Mshari A.
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/8/5
Y1 - 2017/8/5
N2 - Palladium(II) cyanide complexes of thioamides (or thiones) having the general formula PdL2(CN)2, where L = Thiourea (Tu), Methylthiourea (Metu), N, N′-Dimethylthiourea (Dmtu), Tetramethylthiourea (Tmtu), 2-Mercaptopyridine (Mpy) and 2-Mercaptopyrimidine (Mpm) were prepared by reacting K2[PdCl4] with potassium cyanide and thioamides in the molar ratio of 1:2:2. The complexes were characterized by elemental analysis, thermal and spectroscopic methods (IR, 1H and 13C NMR). The structures of three of the complexes were predicted by DFT calculations. The appearance of a band around 2100 cm−1 in IR and resonances around 120–130 ppm in the 13C NMR spectra indicated the coordination of cyanide to palladium(II). More than one resonances were observed for CN− carbon atoms in 13C NMR indicating the existence of equilibrium between different species in solution. DFT calculations revealed that in the case of the palladium(II) complex of Tmtu, the ionic dinuclear [Pd(Tmtu)4][Pd(CN)4] form was more stable than the dimer of mononuclear complex [Pd(Tmtu)2(CN)2] by 0.91 kcal mol−1, while for the complexes of Tu or Mpy ligands, the nonionic [Pd(L)2(CN)2] forms were more stable than the corresponding [Pd(L)4][Pd(CN)4] complexes by 1.26 and 6.49 kcal mol−1 for L = Tu and Mpy, respectively. The complexes were screened for antibacterial effects and some of them showed significant activities against both gram positive as well as gram negative bacteria.
AB - Palladium(II) cyanide complexes of thioamides (or thiones) having the general formula PdL2(CN)2, where L = Thiourea (Tu), Methylthiourea (Metu), N, N′-Dimethylthiourea (Dmtu), Tetramethylthiourea (Tmtu), 2-Mercaptopyridine (Mpy) and 2-Mercaptopyrimidine (Mpm) were prepared by reacting K2[PdCl4] with potassium cyanide and thioamides in the molar ratio of 1:2:2. The complexes were characterized by elemental analysis, thermal and spectroscopic methods (IR, 1H and 13C NMR). The structures of three of the complexes were predicted by DFT calculations. The appearance of a band around 2100 cm−1 in IR and resonances around 120–130 ppm in the 13C NMR spectra indicated the coordination of cyanide to palladium(II). More than one resonances were observed for CN− carbon atoms in 13C NMR indicating the existence of equilibrium between different species in solution. DFT calculations revealed that in the case of the palladium(II) complex of Tmtu, the ionic dinuclear [Pd(Tmtu)4][Pd(CN)4] form was more stable than the dimer of mononuclear complex [Pd(Tmtu)2(CN)2] by 0.91 kcal mol−1, while for the complexes of Tu or Mpy ligands, the nonionic [Pd(L)2(CN)2] forms were more stable than the corresponding [Pd(L)4][Pd(CN)4] complexes by 1.26 and 6.49 kcal mol−1 for L = Tu and Mpy, respectively. The complexes were screened for antibacterial effects and some of them showed significant activities against both gram positive as well as gram negative bacteria.
KW - Antimicrobial
KW - Cyanide
KW - DFT calculations
KW - Palladium(II) complexes
KW - Thioamide
UR - http://www.scopus.com/inward/record.url?scp=85016570904&partnerID=8YFLogxK
U2 - 10.1016/j.molstruc.2017.03.098
DO - 10.1016/j.molstruc.2017.03.098
M3 - Article
AN - SCOPUS:85016570904
SN - 0022-2860
VL - 1141
SP - 204
EP - 212
JO - Journal of Molecular Structure
JF - Journal of Molecular Structure
ER -