Synthesis, Characterization, Crystal Structure And Thermal Stability Of Di-and Triorganotin ( Ⅳ ) Carboxylates

Organotin（Ⅳ） carboxylates have been the subject of interest because of their various structures, significant biotical activities and applications in organic synthesis. In this paper, we introduced the synthesis, structure types and applications of the organotin（Ⅳ） carboxylates, and successfully prepared nine di- and triorganotin （Ⅳ） carboxylates. All complexes were characterized by elemental analysis, IR, 1H NMR, 13C NMR and X-ray crystallography diffraction analysis to elucidate their structures both in solution and in solid state. The thermal stabilities were also investigated. The paper contained the following works:1.Two flexible ligands （HL¹ and HL²） were synthesized by the Williamson reaction. The reaction of di-n-butyltin oxide with the ligands yielded the complexes {[（C₄H₉）₂Sn（3-NO₂-PhCH=N-OCH₂COO）]₂O}₂ （1）and {[（C₄H₉）₂Sn（2,4-Cl-PhCH=N- OCH₂COO）]₂O}₂ （2）, respectively. The complexes all formed a tetrameric ladder structure with a planar Sn2O2 ring, but the coordination geometries of the Sn atoms were different. The hydrogen bonds between adjacent molecules lead to the supramolecular structures.2. Dicarboxylate ligands （H₂L³ and H₂L⁴） that contained the rigid carboxyl and flexible carboxyl were prepared by the Williamson reaction and Knoevenagel- Doebner reaction. The triphenyltin carboxylates [（Ph₃Sn）₃L³·OCH₃]_n （3） and [（Ph_Sn）₃L⁴·OH₂]_n·2CH₃CH₂OH·2H₂O （4） were obtained from the mixture of triphenyltin chloride and the ligands. The complexes were 1D flexible polymer chains and aii the Sn atoms were five-coordinated. Solvent involved in the coordination and there were the hydrogen bonding interaction between the molecules. Complex 3 had good thermal stability.3. The reaction of triphenyltin hydroxide with the 2,4-dichlorophenyl propenoic acid （HL5） and naphthalene-2,6-dicarboxylic acid （H₂L⁶） yielded the complexes [（Ph3Sn）L5]n （5） and [（Ph₃Sn）₂L⁶] （6）. Complex 5 contained a 1d chain, the Sn atom was described as distorted trigonal-bipyramidal geometry. In complex 6, the Sn atom had cis-O2SnC3 configuration. The C-H···O hydrogen bonds and C-H···πstacking played an important role in the supramolecular structure.4. Triorganotin carboxylates [（C6H11）3Sn]₂L⁷ （7）, [（C6H11）3Sn]L8 （8） and {[（C6H11）3Sn]₂L⁹·DMF}·DMF （9） were obtained by the reaction of imide acids （H₂L⁷ and HL8） and 5-amino-isophthalic acid （H₂L⁹） with tricyclohexyltin hydroxide. All complexes had a monomer structure, and the TG curves of the complexes 7 and 8 showed that they had good thermal stability.