Formation of sulfido ciobium complexes through C-S bond activation

Upon reacting (eta5-C5H5)2NbCl2, eta5-C5H5 = Cp, and (Ph)3Sn(SPh), in THF, (eta5-C5H5)2Nb(Cl)(mu-S)Sn(Ph)3(Cl), 1, and (eta5-C5H5)2Nb(S)Cl, 2, were obtained. Complexes 1 and 2 were characterized by IR, ¹H-NMR, 13C-NMR, Mössbauer spectroscopies, elemental analysis as well as by atomic absorption. Hydrolysis of 1 yielded the mu-oxo species, (eta5-C5H5)2Nb(Cl)(mu-O)Sn(Ph)3Cl, 3, which was characterized by IR, ¹H-NMR, 13C-NMR and Mössbauer spectroscopies, elemental analysis, atomic absorption as well as by X-ray crystallography. It crystallizes in the space group Pca2(1) with a = 17.282(3), b = 18.122(4), c = 17.3269(2), V = 5426.2(16) ų, and Z = 8. Additional studies indicated that the complexes were formed as a result of the nucleophilic displacement of the niobium-chloride bond by the thiolate ligand followed by a C-S bond cleavage. The cleavage occurs with an excess of the thiolate compound equal to or greater than 2:1.A reação entre (eta5-C5H5)2NbCl2, eta5-C5H5 = Cp, e (Ph)3Sn(SPh), em THF, originou os complexos (eta5-C5H5)2Nb(Cl)( mi-S)Sn(Ph)3(Cl), 1, e (eta5-C5H5)2Nb(S)Cl, 2. Os complexos 1 e 2 foram caracterizados por espectroscopias no IV, de RMN ¹H, RMN 13C, RMN 119Sn, Mössbauer, análise elementar e absorção atômica. Hidrólise de 1 originou a espécie mi-oxo (eta5-C5H5)2Nb(Cl)(mi-O)Sn(Ph)3Cl, 3, que foi caracterizada por espectroscopias no IV, RMN ¹H, RMN 13C, Mössbauer, análise elementar, absorção atômica bem como por cristalografia de raios-X. O complexo 3 cristaliza no grupo de espaço Pca2(1) com a = 17.282(3), b = 18.122(4), c = 17.3269(2), V = 5426.2(16) ų e Z = 8. Estudos adicionais indicaram que os complexos foram formados como resultado da substituição nucleofílica do cloro da ligação nióbio-cloro pelo ligante tiolato seguido da quebra da ligação C-S. A quebra ocorre com um excesso do composto tiolato igual ou maior que 2:1