Study on the Reactivity of Diphenylthiocarbazone with Mo(V). Synthesis, Characterization and Spectroscopic Studies of Solid Compounds

In this work, we have presented various aspects of the reactivity of diphenylthiocarbazone C₁₃H₁₂N₄S (H₂L, Figure 1) with molybdenum(V) based on the pH of the aqueous metal solution and the ligand metal ratio. The reaction of an ethanolic solution of diphenylthiocarbazone with an aqueous solution of MoCl₅ was investigated at two pH values (2 and 9) for a ligand metal ratio equalling 1. At pH=2, purpuse dimeric complex Mo₂O₃(HL)₂ Cl₂ · 1/2 H₂O was synthesized, whereby HL was the deprotonated species of diphenylthiocarbazone (Complex C1). A similar reaction was conducted at pH 9, leading to the formation of a biradicalar organic compound, C₁₃H₁₀N₄S (Figure 2 and noted R1). The two compounds were characterized by elemental analyses and spectral (IR, UV‐Visible, ESR, ¹H NMR and ⁹⁵Mo NMR) data. The biradicallar ligand was also crystallographically characterized and identified by DRX. This technique reveals no existence of molybdenum and the disappearance of the initially‐existing N‐H groups in free diphenylthiocarbazone. The biradical crystallizes in the monolinic space group C2/C with cell dimensions a=14.736(3) Å, b=12.172(2) Å, c=6.963(4) Å, β=97.23(2) and V=1039.0(8) Å³.

Keywords:

• diphenylthiocarbazone
• molybdenum(V)
• solid compounds
• synthesis