Vibrational and 119Sn Mössbauer Study of Tin Tetrahalide Complexes with Benzofuroxan Derivatives

The reactions of SnX₄ (X = Cl, Br) with benzofuroxan and some substituted derivatives are studied, and the hexacoordinated complexes SnCl₄(Y-C₆H₃N₂O₂)₂ (Y = H, Cl, Me, OMe), and SnBr₄ (Y-C₆H₃N₂O₂)₂ (Y = H, OMe) have been isolated. The adducts are studied by IR, Raman, and ¹¹⁹Sn Mössbauer spectroscopies, which suggest a cis structure (C_2v symmetry) for them. The good correlation between υ Sn? Cl (IR and Raman spectra) and the Mössbauer quadrupole splitting for the SnCl₄ complexes, supports the consistency of the structural assignments. The Mössbauer spectra show resolved quadrupole doublets, in spite of the cis structure of the adducts, which emphasizes the fact that the resolvable or unresolvable nature of the doublets cannot be used confidently to elucidate the structure of tin tetrahalide complexes.