Collect. Czech. Chem. Commun. 1999, 64, 1028-1048

Infrared, 119Sn, 13C and 1H NMR, 119Sn and 13C CP/MAS NMR and Mössbauer Spectral Study of Some Tributylstannyl Citrates and Propane-1,2,3-tricarboxylates

Jaroslav Holečeka,*, Antonín Lyčkab, David Micáka, László Nagyc, György Vankód, Jiří Bruse, S. Shanmuga Sundara Rajf, Hoong Kun Funf and Seik Weng ngg

a Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, 532 10 Pardubice, Czech Republic
b Research Institute for Organic Syntheses, 532 18 Pardubice-Rybitví, Czech Republic
c Department of Inorganic and Analytical Chemistry, Attila Jószef University, H-6701 Szeged, Hungary
d Department of Nuclear Chemistry, Lóránt Ëtvös University, 1518, Budapest, Hungary
e Institute of Macromolecular Chemistry, Academy of Sciences of Czech Republic, 162 06 Prague 6, Czech Republic
f X-Ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM Penang, Malaysia
g Institute of Postgraduate Studies and Research, University of Malaya, 50603 Kuala Lumpur, Malaysia


Six tributylstannyl citrates and three tributylstannyl propane-1,2,3-tricarboxylates of the formula R1C(CH2COOR2)(COOR3)(CH2COOR4) (R1 = OH or H, R2, R3, R4 = H, Bu3Sn, C6H11NH3, (C6H11)2NH2 or (CH2)5NH2) have been synthesised, and their solution and solid-state structures studied by infrared, 1H, 13C and 119Sn NMR, 13C and 119Sn CP/MAS NMR and 119Sn Mössbauer spectroscopies. In non-coordinating solvents, the compounds exist as isolated molecules or ionic-pairs with their tin atoms in pseudotetrahedral environments. In coordinating solvents, the tin atoms in the compounds are five-coordinate owing to the participation of the solvent in bonding; and their trans-trigonal bipyramidal coordination spheres consist of the ipso-carbon atoms of the butyl substituents in equatorial plane, and the solvent molecule and the oxygen atom of the monodentate carboxyl group in axial positions. A part of tributylstannyl groups together with some bidentate bridging carboxylate groups form polymeric chains in the solid state of citrates and propane-1,2,3-tricarboxylates. Also dioxastanna-rings with the participation α-hydroxycarboxylate fragments and one of the tributylstannyl groups occur probably in some citrates in the solid state. The spectroscopic assignment for the citrate has been confirmed by crystal structure analysis.

Keywords: Stannanes; Organotin compounds; Citrates; Propane-1,2,3-tricarboxylates; IR spectroscopy; NMR spectroscopy, 1H, 13C and 119Sn; CP/MAS NMR spectroscopy, 13C and 119Sn; Mössbauer spectroscopy; Crystal structure.