Benzyl Tin Compounds, The Synthesis, Structure And Quantum Chemical Study

The Benzyltin compounds are of great interest for many years because of their abundant structure character,reactivity,high bioactivity and low toxicity. Recent years, people found that the different substituents and their place on aromatic ring have obvious influence on reactivity and crystal structure. In order to understand the influence of substituents' electronic effect and steric effect, six new benzyltin compounds were synthesizedwhich are Ph₃SnO (Ⅰ) , Ph₂SnCl₂·H₂O (Ⅱ) , Ph₃SnI (Ⅲ) , R₂SnCl₂[R=4-Cl-C₆H₅CH₂-](IV), (R₂Sn)₂(O)(Cl)OH[R=4-(CH₃)-C₆H₅CH₂-] (Ⅴ), R₄Sn[2-(OH)-C₆H₅CH₂-] (Ⅵ) .The compounds were characterized by elemental analysis and IR, and the crystal structures were determined by X-ray single crystal defrraction method. The variations on structure and property were also discussed.(1) The complexⅡwas obtained by the reaction of benzyl chloride with tin. Its X-ray crystallography diffraction analyses shows the tin atoms in the crystal structures rendered five-coordinate in a distorted trigonal bipyrarnidal configurations. The two dimensional network structure was constructed by weak interactions…Cl…Sn…and…O…Cl…among the molecules.(2) The complexⅠwas obtained by the reaction of tribenzyltin chloride with NaOH . Its X-ray crystallography diffraction analyses shows the tin atoms in the crystal structures rendered five-coordinate in a distorted trigonal bipyrarnidal configurations. The molecules are packed in the unit cell in one-dimensional chain structure through a weak interaction between the tin atoms and oxygen atoms of an adjacent molecule. The complexⅢwas obtained by the reaction of tribenzyltin chloride with KI. Its X-ray crystallography diffraction analyses shows a distorted tetrahedral geometry around the tin atom. The molecules are packed in the unit cell in one-dimensional chain structure through a weak interaction between the tin atom and iodine atom of an adjacent molecule.(3) The complex IV was synthesized by reaction of p-Cl-PhCH₂Cl with tin . Its X-ray crystallography diffraction analyses shows a distorted tetrahedral geometry around the tin atom. A weak interaction…Cl…Sn… and…Cl…Cl….Which constructs the three dimensional network structure.(4)The complexⅤwas synthesized by reaction of bis(p-methylbenzyl)tin dichloride with KOH. Its X-ray crystallography diffraction analyses shows this compound belongs to centrosymmetric dirner structure mode with a four-membered central endo-cyclic Sn₂O₂ unit shaped the ladder-like structure. Each bridging oxygen atom also connects with an exo-cyclic tin atom. The endo-cyclic and exo- cyclic tin atoms all are six-coordinated and have coordination geometry of distorted octahedron.(5) The complexⅥwas synthesized by reaction of o-chloromethylphenol with tin. Its X-ray crystallography diffraction analyses shows a distorted tetrahedral geometry and the whole molecule shows a screw-like configurations around the tin atom.(6) The quantum chemistry calculation by means of G98W package and taking Lanl2dz basis set were performed on the above complexes. The stabilities of the complexes, some frontier molecular orbital energies and composition characteristics of some frontier molecular orbitals were investigated.