View More View Less
  • 1 A. József University Department of Inorganic and Analytical Chemistry P. O. Box 440 H-6701 Szeged Hungary
  • 2 Bundesanstalt für Materialforschung und-prüfung 12489 Berlin-Adlershof Germany
  • 3 University of Bergen Department of Chemistry Allegaten 41 N-5007 Bergen Norway
  • 4 Otto-von-Guericke University Department of Chemistry Universitätplatz 2 Geb. MD-39106 Magdeburg Germany
Restricted access

Abstract  

Fourteen complexes of di-n-butyltin(IV)2+ cations with flavonoid glycosides (rutin, hesperidin, 2′,4′,3-trihydroxy-5′,4-dimetoxychalkone 4-rutinoside) and flavonoid aglycones (quercetin, morin, hesperitin and sorte flavones) were prepared. The composition of the complexes was determined by standard analytical methods. The results showed that complexes containing diorganotin(IV)2+ moiety and the ligand in 1∶1, 2∶1 or 3∶1 ratio are formed. The FTIR spectra were consistent with the presence of Sn-O (phenol or carbohydrate) vibration in the compounds. The structure of the complexes was measured by Mössbauer spectroscopy. Comparison of the experimental quadrupole splitting with those calculated on the basis of partial quadrupole splitting concept revealed that the complexes are of four types: with the central tin atoms surrounded by donor atoms in a purely trigonal-bipyramidal, octahedral+trigonal-bipyramidal, trigonal-bipyramidal+tetrahedral and octahedral+tetrahedral arrangement. This procedure also distinguished between the different structural isomers of both trigonal-bipyramidal and octahedral complexes. Conclusions could therefore be drawn on the factors determining which of the isomers are formed in the systems. The Mössbauer parameters obtained for organotin(IV)-flavonoid complexes were compared with those measured for organotin(IV)-carbohydrate complexes.