Synthesis, Characterization And Crystal Structure Study Of Novel Organotin(Ⅳ) Carboxylates

Organotin carboxylates have attracted considerable attention due to their wide applications in many fields, for example as pesticidal, bactericidal and antitumor agents. Therefore, it is very important to synthesize novel organotin carboxylates and study their properties.In this paper, five carboxylic acids, 2-(4-methylbenzoyl)benzoic acid (HL₁), 2-(2,4-diethylbenzoyl)benzoic acid (HL₂), 2-(4-isopropylbenzoyl)benzoic acid (HL₃), 2-(4-chlorobenzoyl)benzoic acid (HL₄) and trans 12-Benzoyl-9,10-dihydro-9,10- ethanoanthracene-11-carboxylic Acid (HL₅) were prepared by the Friedel-Crafts acylation of toluene,1,3-diethylbenzene,cumene,1-chlorobenzene and isobenzofuran-1,3-dione, 9,10-dihydroanthracene-9,10-α,β-dihydrofuran-11,13-dione. Six novel organotin arboxylates, {[n-Bu₂Sn(L₁)₂]₂O}₂ (1), {[n-Bu₂Sn(L₂)₂]₂O}₂ (2), {[n-Bu₂Sn(L₃)₂]₂O}₂ (3), {[n-Bu₂Sn(L₄)₂]₂O}₂ (4), [(n-Bu₂Sn)₄(L₅)₂O₂(OC₂H₅)₂] (5) and [(C₆H₅)₃Sn(L₅)] (6) were prepared by the reaction of n-Bu2SnO, Ph3SnOH and the carboxylic acids above.The ligands and their metal complexes were characterized by elemental analysis, 1H NMR and FT-IR spectroscopy, and the structures of the complexes were determined by single crystal X-ray diffraction analysis. The single crystal X-ray diffraction analysis show that all structures of (1), (2), (3), (4) and (5) invole a centrosymmetric structure which built up around a planar, four-membered cyclic Sn₂O₂ unit. Complexes of (1), (2) and (4) adopt the type I structure, while the complex (3) Adopts the type IV, and (5) the type V. In the molecular structure of (5) the additional links between the exo-cyclic Sn and endo-cyclic Sn atom are provided by bidentate deprotonated ethanol that form the asymmetrical bridges and result in a ladder type structure which contains three four-membered rings. In the molecular structure of (6), the tin atom is four coordinated and adopted the distort tetrahedron structure. The bioactivity of complex (1) was preliminary studied and the antibacterial antitumor activity tests show that it exhibits a good bioactivity.