| Organotin(IV) compounds are attracting more and more interests due to their applications in industry, agriculture and biology especially in fields of organic synthesis, catalyst, pharmaceutics, stabilization for PVC, anti-contamination, antiseptic and etc. The range of its research is expanding constantly, including the organometallic chemistry, coordination chemistry, biochemistry and pharmacology, etc. and it becomes the front field that has the development prospect.From the view of coordination chemistry, the bidentate or multi-dentate ligands with N, O and S donor atoms may benefit the construction of more complicated and interesting structures that have multiple tin atoms and molecular structure dimension, increased coordination number as well as diversified coordination mode. While on the other hand, the ligands containing the above donor atoms are not only relevant to the material of life, but also have complicated and variable behavior of coordination. Out of above considerations, we carried out a series of research on syntheses, characterization and supramolecular structure of organotin derivatives from ligands containing the hecarboxylic acid and thiol. The main contributions of the thesis are as follows:1. Investigations on the reactions of triorganotin with 2,2'-bipyridine-4,4'-dicarboxylic acid, benzimidazole-5,6-dicarboxylic acid. Seven new crystals of organotin compounds were obtained and have been characterized by elemental analysis, IR, NMR and X-ray diffraction. The results show that: In the triorganotin derivatives of 2,2'-bipyridine-4,4'-dicarboxylic acid, the products are dinuclear monomers or coordination polymers depending on the different substitutes attached on tin atoms. When the R=Me, n-Bu, the products are 2D coordination polymers; while the R=Ph, Bz, the products are dinuclear monomers. The supermolecular structures of complexes 1 and 2 are formed by C-H···N and O-H···O, respectively. For complexes 5-7, Three types of di- and trimethyltin(IV) polymers have been synthesized by the reaction of trimethyltin chloride with benzimidazole-5,6-dicarboxylic acid under three different experimental conditions. The 2D network structure was formed in the solution of benzene, the 3D corrugated polymer was formed in the solution of methanol, while under solvothermal condition, we obtained a 1D helical chain struvture, the central tin atom are seven-coordinated.2. Investigations on the reactions of organotin with five displaced nicotinic or isonicotinic acid: Twenty-two new organotin compounds were obtained and characterized by elemental analysis, IR, NMR spectroscopy, eighteen of them were also characterized by X-ray crystallographic diffraction analyses. The results show that: In the diorganotin derivatives of 2-chloroisonicotinic acid acid, all the complexes are tetranuclear centrosymmetric structures based on a centrosymmetric Sn2O2 unit. Owing to the local resistance, tetranuclear atructures are different, derivatives of diphenyl, dibenzyl and dibutyltin are tetranuclear with two ligands, while the derivatives of dimethyltin have four ligands. For complex 11, under solvothermal condition, we obtained a mixed tri- and dimethyltin with six-nuclear ladder structure. Although the nitrogen atom did not coordinate with tin atom, the supermolecular of 1D,2D and 3D structures were obtained by the intermolecular C-H···N, O-H···N hydrogen bonding. In the triorganotin derivatives of 2-hydroxynicotinic acid, owing to the local resistance, the derivatives of triphenyl, tribenzyltin are also monomers, while the derivative of trimethyl is a 1D polymer. For the derivatives of tributyltin, we obtained a novel mixed tri- and dibutyltin macrocyclic complex solvothermal condition. In the triorganotin derivatives of 5-hydroxynicotinic acid, 6-hydroxynicotinic acid and 2-hydroxyisonicotinic acid, all the complexes were obtained in the ratio of ligand: EtONa: R3SnCl = 1:1:1 except complex 26. The central tin atoms are all five-coordinated with trigonal bipyramid. All the complexes are 1D polymers except complex 32, complex 32 is a 42-membered macrocycle containing six tin atoms. For complex 26, we obtained it by the ratio of 5-hydroxynicotinic acid: EtONa: R3SnCl = 1:2:2. It is also a 1D polymer, but it cannot self-assemble anymore because of the coordination of water molecule.3. Investigations on the reactions of triorganotin with two heterocyclic thiol: 6-(dibutylamino)-1,3,5-triazine-2,4-dithiol and 5-Amino-1,3,4-thiadiazole. Eight new organotin compounds were obtained and characterized by elemental analysis, IR, NMR spectroscopy analysis, four of them were also characterized by X-ray crystallographic diffraction analyses. The results show that: For complexes 30-33, triphenyltin and tribenzyltin complexes were monomeric four-coordinated structures by the S atom coordinating to tin atom, while trimethyltin and n-tributyltin were 1D polymers. For complexes 34-37, the ligand act as N single-dentate or S,N bi-dentate owing to the substitutes attached on tin atoms. Triphenyltin and tribenzyltin complexes were monomeric four-coordinated structures by the S atom coordinating to tin atom, while trimethyltin and n-tributyltin complexes can form macrocyclic complex by N→Sn coordination.It is worth to note that through these synthesis and structural characterization, we found that on the basis of different mole ratio, the environment of Sn atom is complicated and variable correspondingly and non-bond weak interaction, hydrogen bonding andπ-πstacking interaction may benefit the construction of 1D chain or 2D layer structures of the organotin complexes. And under a certain condition, some structure can recognize special molecules and proceed self-assemblement to form supramolecules. These structural information may throw new light in the structure-effect relationship of the organotin(IV) compounds.
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