resumo
In an effort to utilize [Co(phen)(2)CO3](+) cation as a new host for mono-, di- and tri-substituted nitrophenolate anions, red coloured crystals of composition [Co(phen)(2)CO3](onp)center dot 2H(2)O, [Co(phen)(2)Co-3](pnp), orange coloured precipitated product of [Co(phen)(2)CO3](dnp)center dot 4.5H(2)O (which gave red coloured crystals from acetone-water mixture) and orange-yellow coloured precipitated product of (Co(phen)(2)CO3](tnp) were obtained in good yields by reacting sodium salts of o-nitrophenol, p-nitrophenol 2,4-dinitrophenol and 2,4,6-trinitrophenol with [Co(phen)(2)CO3]Cl center dot 5H(2)O, respectively in 1:1 molar ratio in aqueous medium. These cobalt(III) complex salts have been characterized by elemental analyses, spectroscopic techniques (UV/Visible, IR and NMR) and conductance measurements. Single crystal X-ray structure determination of [Co(phen)(2)CO3](onp)center dot 2H(2)O and [Co(phen)(2)CO3](dnp)center dot 4.5H(2)O revealed the presence of discrete ions and lattice water molecules in the solid state. A strong network of hydrogen bond interactions through the weak second sphere coordination (C-H center dot center dot center dot O (phenolate), C-H center dot center dot center dot O (nitro), and strong interactions of type O-H center dot center dot center dot O (water) besides the electrostatic interactions play a very important role in stabilizing the crystal lattice. The studies indicated that complex cation. [Co(phen)(2)CO3](+) may preferentially bind nitrophenolate ions in the aqueous medium. (C) 2008 Elsevier B.V. All rights reserved.
palavras-chave
SPECTROSCOPIC CHARACTERIZATION; COMPLEXES; RECOGNITION; PACKING
categoria
Chemistry
autores
Singh, A; Sharma, RP; Brandao, P; Felix, V; Venugopalan, P
nossos autores
Paula Cristina Ferreira da Silva Brandão
Investigador Auxiliar
Vítor Félix
Professor Associado com Agregaçãoagradecimentos
The authors gratefully acknowledges the financial support of CSIR vide Grant no-01(2020) 2005/EMR-II.