resumo
New chiral metal organic frameworks, assembled from Y(III), Na(I), and chiral flexible-achiral rigid dicarboxylate ligands, formulated as [NaY(Tart)(BDC)(H(2)O)(2)] (1) and [NaY(Tart)(biBDC)(H(2)O)(2)] (2) (H(2)Tart = Tartaric acid; H(2)BDC = Terephthalic acid; H(2)biBDC = Biphenyl-4,4'-dicarboxylic acid), were obtained as single phases under hydrothermal conditions. Their structures were solved by single-crystal X-ray diffraction (XRD), and characterized by (13)C CPMAS NMR, thermal analyses (thermogravimetry-mass spectrometry (TG-MS) and differential scanning calorimetry (DSC)), and X-ray thermodiffractometry. Both compounds crystallize in the orthorhombic chiral space group C222(1) with a = 6.8854(2) angstrom, b = 30.3859(7) angstrom, c = 7.4741(2) angstrom for 1, and a = 6.8531(2) angstrom, b = 39.0426(8) angstrom, c = 7.4976(2) angstrom for 2.1 and 2 are layered structures whose three-dimensional stability is ensured by strong hydrogen bond interactions. The dehydration of both compounds is accompanied by phase transformation, while the spontaneous rehydration process is characterized by different kinetics, fast in the case of 1 and slow for 2.
palavras-chave
EARTH COORDINATION POLYMERS; ADSORPTION PROPERTIES; SUPERCONDUCTIVE MATERIALS; LUMINESCENT PROPERTIES; GAS-ADSORPTION; HYDROGEN ADSORPTION; CRYSTAL-STRUCTURE; CARBOXYLIC-ACIDS; BUILDING-BLOCKS; POROUS MATERIAL
categoria
Chemistry
autores
Amghouz, Z; Roces, L; Garcia-Granda, S; Garcia, JR; Souhail, B; Mafra, L; Shi, FN; Rocha, J
nossos autores
Projectos
Nanogotas de Água em Materiais Microporosos e Híbridos Orgânicos-Inorgânicos (PTDC/QUI/65805/2006)
agradecimentos
We thank financial support from Spanish Ministerio de Educacion y Ciencia (ACI20073448000507, MAT2006-01997, Factoria de Crsitalizacion Consolider Ingenio 2010 and FPI Grant BES-2007-14340 to Z.A.), Portuguese Fundactio para a Ciencia e a Tecnologia (PTDC/QUI-QUI/100998/2008 and PTDC/QUI/65805/2006), FSE, and FEDER. The authors are also grateful to Prof. Jose Gimeno for helping us to carry out the catalysis studies.