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Emmanuel Blas Patricio-Rangel Margarita Tlahuextl Hugo Tlahuext Antonio Rafael Tapia-Benavides 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(4):322-327
The synthesis and characterization of two new 1,3,5‐triazines containing 2‐(aminomethyl)‐1H‐benzimidazole hydrochloride as a substituent are reported, namely, 2‐{[(4,6‐dichloro‐1,3,5‐triazin‐2‐yl)amino]methyl}‐1H‐benzimidazol‐3‐ium chloride, C11H9Cl2N6+·Cl? ( 1 ), and bis(2,2′‐{[(6‐chloro‐1,3,5‐triazine‐2,4‐diyl)bis(azanediyl)]bis(methylene)}bis(1H‐benzimidazol‐3‐ium)) tetrachloride heptahydrate, 2C19H18ClN92+·4Cl?·7H2O ( 2 ). Both salts were characterized using single‐crystal X‐ray diffraction analysis and IR spectroscopy. Moreover, the NMR (1H and 13C) spectra of 1 were obtained. Salts 1 and 2 have triclinic symmetry (space group P) and their supramolecular structures are stabilized by hydrogen bonding and offset π–π interactions. In hydrated salt 2 , the noncovalent interactions yield pseudo‐nanotubes filled with chloride anions and water molecules, which were modelled in the refinement with substitutional and positional disorder. 相似文献
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Bernabé-Pineda M Ramírez-Silva MT Tapia-Benavides R Rojas-Hernández A 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(5):1071-1076
The importance assigned to chelating agents in diverse areas has impelled studies concerning their development as related to metal ions representing a biological concern. The synthesis of di-isopropyliminodiacetoamide (D) is presented in this work. The acidity constant obtained for D was pKa = 5.79 +/- 0.04 with the aid of program SUPERQUAD. The equilibrium constants for D with Cu(II) were obtained with the aid of program SQUAD for CuD2+ and CuD2(2)+ species giving log beta1 = 4.795 +/- 0.002 and log beta2 = 8.374 +/- 0.004, respectively. 相似文献
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Francisco Pérez-García Antonio R. Tapia-Benavides Hugo Tlahuext Alejandro Álvarez Margarita Tlahuextl 《Structural chemistry》2006,17(4):359-366
This paper describes the structural studies of 2-phenyl-9,9′-dimethyl-2,2′-spirobis(1,3,2-λ5-benzoxazarsoline) 5, 2-phenyl-8,8′-dimethyl-2,2′-spirobis(1,3,2-λ5-benzoxazarsoline) 6 by 1H,13C,15N NMR in [2H6]DMSO and CDCl3. The solid state studies were made by X-ray experiments. Infrared spectroscopy was obtained in CDCl3 and the vibrational signals were assigned using DFT calculations. The nature of the As–N, As–C and As–O bonds in these compounds was established by NBO studies. 相似文献
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The first examples of 1,7,1,4,7,8-dialkyltriazaborabicyclo[3.3.0]octanes 1–3 [R = isopropyl ( 1 ), R = 1-phenylbenzyl (2) , R = 1-methylbenzyl (3) ] are reported. The bulky substituents prevent dimerization and make the syntheses feasible. The structures and conformations of the new compounds were studied by NMR spectroscopy. A chiral bicycle 3 (R,R) was also prepared. 相似文献
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Margarita Tlahuextl Liliana Aguilar-Castro Carlos Camacho-Camacho Rosalinda Contreras Antonio R. Tapia-Benavides 《Heteroatom Chemistry》2004,15(2):114-120
This paper describes the synthesis and structural studies of N-(p-toluenesulfonyl)-amino acid 3,5-di-tert-butyl-2-phenolamides by 1H, 13C, and 15N. The presence of intra- and intermolecular hydrogen bonds were studied by variable temperature NMR spectroscopy. The molecular structure of two amides in the solid state was determined by X-ray diffraction experiments. The results show that tert-butyl substituents in the phenolic ring have important effects in the nature of hydrogen bonds and conformation of these amides. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:114–120, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10223 相似文献
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Elidia Gutiérrez-Sanjuan Margarita Tlahuextl Martha Falcón-León Hugo Tlahuext Yolanda Marmolejo-Santillán Antonio R. Tapia-Benavides 《Structural chemistry》2014,25(5):1385-1393
The complexes trans-bis[2-(aminomethyl)-1H-benzimidazole-κ 2 N′,N″]diaquazinc(II) dichloride dihydrate 1 and trans-bis[2-(aminomethyl)-1H-benzimidazole-κ 2 N′,N″]aquazinc(II) dichloride dihydrate 2 were synthesized selectively by the promotion of O–H···Cl hydrogen bond interactions. The hexacoordinated complex 1 was synthesized at pH 4.5. The dilution of 1 in deionized water produced the pentacoordinated complex 2. NMR and vibrational spectroscopies corroborated the presence of these compounds. Moreover, mass spectrometry and thermogravimetric (TGA) studies demonstrated that chloride ions and crystallization water molecules are essential for the stabilization of 1 but not for complex 2. X-ray diffraction crystallography studies indicated that the presence of two water molecules bonded to the Zn atom elongated all of the coordination bonds. The incidence of a network of hydrogen bond interactions compensates for the unstable hexacoordination. Natural bond orbital (NBO) and quantum theory of atoms in molecules (QTAIM) studies of the crystal structures of 1 and 2 were used to explain the nature of the coordination bonds and the complexes’ stability . 相似文献
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Aguilar-Castro Liliana Tlahuextl Margarita Tapia-Benavides Antonio R. Alvarado-Rodríguez José Guadalupe 《Structural chemistry》2004,15(3):215-221
N-(p-Toluenesulfonyl)-glycine 7 and analogous derivatives of d,l-alanine 8, L-valine 9, L-leucine 10, L-isoleucine 11, and L-phenylalanine 12 were synthesized by condensation of the amino acid with p-toluenesulfonyl chloride. The presence of intermolecular hydrogen bonding was established by variable NMR spectroscopy. The molecular structure and intermolecular interactions of N-(p-toluenesulfonyl)–d,l-alanine and N-(p-toluenesulfonyl)–L-valine were corroborated by X-ray diffraction (XRD) experiments. 相似文献
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