Penta- and heptacoordinated tin(IV) compounds derived from pyridine Schiff bases and 2-pyridine carboxylate: Synthesis and structural characterization
Por:
Ramirez-Jimenez, A, Gomez, E, Hernandez, S
Publicada:
15 ago 2009
Resumen:
The synthesis of the Sn(IV)-complexed, Schiff base derivatives 1a-1l, prepared in one pot by the reaction of 2-amino-4-R-phenol (R = H, Me, Cl, NO(2)), 2-pyridinecarboxaldehyde, 2-picolinic acid and dimethyl-, dibutyl-, and diphenyltin oxides, is described. The complexes were characterized by IR, MS, (1)H, (13)C, (119)Sn NMR. Suitable crystals of 1e and 1h enabled us to use X-ray diffraction to determine their molecular structures, which exhibited pentagonal-bipyramidal geometries where the butyl groups occupied the axial positions whereas the nitrogen and the oxygen atoms occupied the equatorial positions. The reaction of the Schiff base 2 with dibutyltin oxide led to the pentacoordinated complex, 2h, through the addition of methanol to the C=N bond. An unusual reduction-oxidation reaction took place by the reaction of 2-amino-4-nitro-phenol, dibutyltin oxide and 2-pyridinecarboxaldehyde, which produced the corresponding amine, 3h, and the amide, 4h, tin(IV) derivatives. Both structur
Filiaciones:
Univ Nacl Autonoma Mexico, Inst Quim, Mexico City 04510, DF, Mexico
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