102493-31-2Relevant academic research and scientific papers
Discrete, dimeric, and polymeric structures of triphenyltin esters of chlorobenzoic acids
Holmes, Robert R.,Day, Roberta O.,Chandrasekhar,Vollano, Jean F.,Holmes, Joan M.
, p. 2490 - 2494 (2008/10/08)
Reaction of bis(triphenyltin) oxide with o- and p-chlorobenzoic acids leads to the formation of the respective esters Ph3Sn(p-ClC6H4CO2) (1) and Ph3Sn(o-ClC6H4CO2) (2). The hydrated etherate of 2, [Ph3Sn(o-ClC6H4CO2)] 2·H2O·Et2O (3), also is formed. X-ray crystallographic analysis reveals that 1 exists as a discrete, intramolecularly five-coordinated entity best described as a distorted tetrahedron with oxygen atoms bridging cis positions, whereas 2 has a one-dimensional polymeric formulation containing tin in a trigonal bipyramid with the axial positions occupied by oxygen atoms. The conformation around tin in 3 is similar to that in 2, but a dimeric composition resulted, giving an end-stopped, hydrogen-bonded hydrate. Esters 2 and 3 are the first examples containing triphenyltin with oxygen donor ligands in this geometrical form. The variations in observed geometrical form in the solid state among 1-3 are attributed to steric and electronic effects of the o-chloro group in 2 and 3 tending to equalize the carboxyl group carbon-oxygen double-bond character. This results in more nearly equal oxygen-tin bond properties that favor the trans oxygen coordination found in the structures of 2 and 3. Compound 1 crystallizes in the monoclinic space group C2/c (Z = 8) with a = 16.995 (4) A?, b = 11.403 (4) A?, c = 24.343 (8) A?, and β = 103.10 (2)°. Compound 2 crystallizes in the monoclinic space group P21/n (Z = 4) with a = 9.190 (2) A?, b = 11.407 (4) A?, c = 21,088 (3) A?, and β = 101.87 (1)°. Compound 3 crystallizes in the monoclinic space group P21/c (Z = 4) with a = 12.826 (5) A?, b = 17.759 (3) A?, c = 22.812 (6) A?, and β = 105.63 (2) A?. The final conventional unweighted residuals were 0.035 (1), 0.032 (2), and 0.037 (3).
