Inorganic compounds containing the trifluoroacetate group. Part III. Reactions of bis(trifluoroacetato)divinyltin with N-, O-, or N- and O-donor ligands, and the crystal structure of (2,2′-bipyridyl)bis(trifluoroacetato)divinyltin

Abstract

The addition complexes [(H₂C:CH)₂Sn(O₂C·CF₃)₂L_n][n= 1, L = 2,2′-bipyridyl, 1,10-phenanthroline, NN′-ethylenebis(salicylidineimine) or ethylene-1,2-diamine; n= 2, L = triphenylphosphine oxide or hexamethylphosphoramide] have been prepared and characterised. These compounds (II)–(VII) all contain octahedrally co-ordinated tin(IV) with two unidentate trifluoroacetato-groups. This geometry has been confirmed by X-ray crystallography for the 2,2′-bipyridyl addition complex (II) which crystallises in the monoclinic space group P2₁/c, with Z= 4 in a unit cell of dimensions a= 8.04, b= 15.39, c= 17.37 Å, and β= 106.6°. The structure has been determined from three-dimensional X-ray diffraction data by Patterson and Fourier methods, and refined by least-squares to a final R of 0.070 (for 2194 diffractometer intensities). (II) Exists as discrete molecules in the crystal; some mean distances are: Sn–O 2.21(4), Sn–C 2.10(2)(two mutually transσ-bonded vinyl groups), and Sn–N 2.34 ± 0.01 Å, [(H₂C:CH)₂Sn(O₂C·CF₃)₂] reacts with 8-hydroxyquinoline or sodium acetylacetonate to afford [(H₂C:CH)₂Sn(ONC₉H₇)(O₂C·CF₃)] or [(H₂C:CH)₂Sn(O₂C₅H₇)₂] respectively, and with carboxylic acids to produce the corresponding [Sn(O₂CR)₄] derivatives.