Synthesis,Spectroscopic, and X‐Ray Diffraction Studies of cis‐Dichlorobis(4‐propanoyl‐2,4‐dihydro‐5‐methyl‐2‐phenyl3 H‐pyrazol‐3‐onato) Tin(IV)

Reaction between an aqueous ethanol solution of tin(II) chloride and that of 4‐propanoyl‐2,4‐dihydro‐5‐methyl‐2‐phenyl‐3 H‐pyrazol‐3‐one in the presence of O₂ gave the compound cis‐dichlorobis(4‐propanoyl‐2,4‐dihydro‐5‐methyl‐2‐phenyl‐3 H‐pyrazol‐3‐onato) tin(IV) (C₂₆H₂₆N₄O₄)SnCl₂]. The compound has a six‐coordinated Sn^IV centre in a distorted octahedral configuration with two chloro ligands in cis position. The tin atom is also at a pseudo two‐fold axis of inversion for both the ligand anions and the two cis‐chloro ligands. The orange compound crystallizes in the triclinic space group P 1 with unit cell dimensions, a = 8.741(3) Å, b = 12.325(7) Å, c = 13.922(7) Å; α = 71.59(4), β = 79.39(3), γ = 75.18(4); Z = 2 and D_x = 1.575 g cm^–3. The important bond distances in the chelate ring are Sn–O 2.041 to 2.103 Å], Sn–Cl 2.347 to 2.351 Å], C–O 1.261 to 1.289 Å] and C–C 1.401 Å] the bond angles are O–Sn–O 82.6 to 87.7° and Cl–Sn–Cl 97.59°. The UV, IR, ¹H NMR and ¹¹⁹Sn Mössbauer spectral data of the compound are reported and discussed.