Synthesis, structural characterization, and in vitro antimicrobial properties of salicylate and pyrazoline complexes of bismuth(III)

Abstract

Displacement reactions of dichlorobismuth(III)pyrazolinates with oxygen donors such as sodium salicylate and acetate in 1 : 1 and 1 : 2 molar ratio in refluxing anhydrous benzene yields (C₁₂H₁₅N₂OX)Bi(C₆H₄O₃), (CH₃COO)BiCl(C₁₅H₁₂N₂OX), and (CH₃COO)₂Bi(C₁₅H₁₂N₂OX) [C₁₂H₁₅N₂OX = 3(2′-hydroxyphenyl)-5-(4-X-substituted phenyl) pyrazoline X = H in 1,5,9, CH₃ in 2,6,10, OCH₃ in 3,7,11, and Cl in 4,8,12, respectively, (C₆H₄O₃) = salicylate and (CH₃COO) = acetate]. Newly synthesized derivatives are brown solids, soluble in organic solvents like benzene, chloroform, and acetone. The compounds have been characterized by elemental analyses (C, H, N, Cl, and Bi), molecular weight measurements, and spectral (IR, ¹H NMR, ¹³C NMR) studies. The (C₁₂H₁₅N₂OX) and (C₆H₄O₃) are bidentate while (CH₃COO) is monodentate to bismuth(III), leading to a distorted trigonal bipyramidal structure. The complexes were screened against different bacteria and fungi showing potential antibacterial and antifungal activities.

Keywords:

• Dichlorobismuth(III)pyrazolinates
• Pyrazoline
• Salicylate
• Carboxylate
• Antimicrobial

Acknowledgments

J.S. Solanki is thankful to UGC for providing Rajeev Gandhi National Fellowship as SRF for the PhD Degree. We are also thankful to RSIC, CDRI Lucknow, India, for providing the spectral and analytical data.