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Chao Huang - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of a host–guest complex of the tris-urea receptor, 3-(4-nitrophenyl)-1,1-bis{2-[3-(4-nitrophenyl)ureido]ethyl}urea, that encapsulates hydrogen-bonded chains of dihydrogen Phosphate Anions with separate tetra-n-butylammonium
Acta Crystallographica Section E: Crystallographic Communications, 2019Co-Authors: Ruyu Wang, Shoujian Li, Chao HuangAbstract:The title compound, C25H25N9O9·C16H36N+·H2PO4− (I) or (C25H25N9O9)·(n-Bu4N+)·(H2PO4−) (systematic name: 3-(4-nitrophenyl)-1,1-bis{2-[3-(4-nitrophenyl)ureido]ethyl}urea tetrabutylammonium dihydrogen Phosphate), comprises a tris-urea receptor (R), a dihydrogen Phosphate Anion and a tetra-n-butylammonium cation. It crystallizes with two independent formula units in the asymmetric unit. The conformations of the two tris-urea receptors are stabilized by N—H⋯O and C—H⋯O intramolecular hydrogen bonds. Each dihydrogen Phosphate Anion has two O—H⋯O intermolecular hydrogen-bonding interactions with the other dihydrogen Phosphate Anion. Inversion-related di-Anion units are linked by further O—H⋯O hydrogen bonds, forming a chain propagating along the a-axis direction. Each dihydrogen Phosphate Anion makes a total of four N—H⋯O(H2PO4−) hydrogen bonds with two ureido subunits from two different tris-urea receptors, hence each tris-urea receptor provides the two ureido subunits for the encapsulation of the H2PO4− hydrogen-bonded chain. There are numerous intermolecular C—H⋯O hydrogen bonds present involving both receptor molecules and the tetra-n-butylammonium cations, so forming a supramolecular three-dimensional structure. One of the butyl groups and one of the nitro groups are disordered over two positions of equal occupancy.
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Crystal structure of a host-guest complex of the tris-urea receptor, 3-(4-nitro-phen-yl)-1,1-bis-{2-[3-(4-nitro-phen-yl)ureido]eth-yl}urea, that encapsulates hydrogen-bonded chains of di-hydrogen Phosphate Anions with separate tetra-n-butyl-ammonium
Acta crystallographica. Section E Crystallographic communications, 2019Co-Authors: Ruyu Wang, Shoujian Li, Chao HuangAbstract:The title compound, C25H25N9O9·C16H36N+·H2PO4 - (I) or (C25H25N9O9)·(n-Bu4N+)·(H2PO4 -) (systematic name: 3-(4-nitro-phen-yl)-1,1-bis-{2-[3-(4-nitro-phen-yl)ureido]eth-yl}urea tetra-butyl-ammonium di-hydrogen Phosphate), comprises a tris-urea receptor (R), a di-hydrogen Phosphate Anion and a tetra-n-butyl-ammonium cation. It crystallizes with two independent formula units in the asymmetric unit. The conformations of the two tris-urea receptors are stabilized by N-H⋯O and C-H⋯O intra-molecular hydrogen bonds. Each di-hydrogen Phosphate Anion has two O-H⋯O inter-molecular hydrogen-bonding inter-actions with the other di-hydrogen Phosphate Anion. Inversion-related di-Anion units are linked by further O-H⋯O hydrogen bonds, forming a chain propagating along the a-axis direction. Each di-hydrogen Phosphate Anion makes a total of four N-H⋯O(H2PO4 -) hydrogen bonds with two ureido subunits from two different tris-urea receptors, hence each tris-urea receptor provides the two ureido subunits for the encapsulation of the H2PO4 - hydrogen-bonded chain. There are numerous inter-molecular C-H⋯O hydrogen bonds present involving both receptor mol-ecules and the tetra-n-butyl-ammonium cations, so forming a supra-molecular three-dimensional structure. One of the butyl groups and one of the nitro groups are disordered over two positions of equal occupancy.
Jonathan L Sessler - One of the best experts on this subject based on the ideXlab platform.
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non cyclic formylated dipyrromethanes as Phosphate Anion receptors
Chemical Science, 2016Co-Authors: Murat K Deliomeroglu, Vincent M Lynch, Jonathan L SesslerAbstract:New tetrakis- and hexakis(1H-pyrrole-2-carbaldehyde) Anion receptors are described. The Anion binding properties of these receptors were studied in organic media and in the solid state. The receptors displayed good affinity for the dihydrogenPhosphate and pyroPhosphate Anions (as the tetrabutylammonium salts) in chloroform even in the presence of a polar protic solvent, methanol. Solution phase spectroscopic analyses proved consistent with the binding mode seen in single crystal structural studies of the dihydrogenPhosphate and pyroPhosphate complexes and provided support for the contention that these receptors undergo conformational reorganization in order to accommodate the bound oxoAnions both in chloroform solution and in the solid state.
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new porphyrin derivatives for Phosphate Anion sensing in both organic and aqueous media
Chemical Communications, 2014Co-Authors: Joao M M Rodrigues, Andreia S F Farinha, Paulino V Muteto, Sandra M Woranoviczbarreira, Maria G P M S Neves, Jose A S Cavaleiro, Augusto C Tome, Teresa M S R Gomes, Jonathan L SesslerAbstract:New porphyrin-based Anion receptors have been prepared from meso-tetrakis(pentafluorophenyl)porphyrin (TPPF20) and diamine derivatives. These receptors (compounds 1–3) interact preferentially with Phosphate Anions both in organic solutions and in basic aqueous media when coated on gold piezoelectric quartz crystals. A single crystal X-ray structure of the bis-HF complex of a imine derivative of 1 was obtained; it serves to highlight the main interactions between the Anion and cation receptors in the solid state.
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diindolylquinoxalines effective indole based receptors for Phosphate Anion
Journal of the American Chemical Society, 2006Co-Authors: Jonathan L Sessler, Vincent M LynchAbstract:The synthesis of a new series of 2,3-diindol-3‘yl quinoxalines (DIQ), as well as a comparison of their Anion recognition properties to those of our previously reported pyrrole based sensors, 2,3-dipyrrol-2‘yl quinoxalines, is reported. To the best of our knowledge, this new DIQ system represents the first example of a free-standing indole-based small molecule receptor for which evidence of Anion binding is available both in solution and in the solid-state. It also provides one of the few structurally characterized neutral receptor−dihydrogen Phosphate complexes. This work thus serves to demonstrate the utility of indoles as an Anion recognition motif.
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water soluble sapphyrins potential fluorescent Phosphate Anion sensors
Organic and Biomolecular Chemistry, 2003Co-Authors: Jonathan L Sessler, Julian M Davis, Vladimir Kral, Thomas Kimbrough, Vincent M LynchAbstract:As part of an ongoing effort to study the Anion binding properties of sapphyrins in various media, a number of previously reported water solubilized sapphyrins were studied in methanol and in buffered, neutral aqueous solutions and found to undergo self-aggregation under these solution phase conditions. The nature of the species produced as the result of self-aggregation and the processes leading to their formation were studied via UV-vis absorbance and fluorescence spectroscopy. In previous work (V. Kral, H. Furuta, K. Shreder, V. Lynch, and J. L. Sessler, J. Am. Chem. Soc., 1996, 118, 1595–1607.) it was found that the addition of Phosphate-type Anions to water soluble sapphyrins at pH 6.1 gives rise to visible spectroscopic changes consistent with the binding to the aggregated form and the concurrent formation of an Anion-bound dimer with effective equilibrium constants on the order of 100–300 M−1. In this study we show that at high Phosphate-to-sapphyrin ratios in neutral, buffered aqueous solutions further deaggregation occurs to produce an Anion-bound monomeric form. This highly fluorescent species is formed with effective equilibrium constants on the order of 6–19 M−1 leading to considerations that sapphyrins could function as fluorescent Phosphate Anion sensors. In an effort to modulate the deaggregation properties, several new sapphyrin derivatives bearing two meso aryl substituents were prepared and studied. The aggregation properties of these latter systems were analyzed in methanol and, in the case of one water solublized system, in neutral aqueous media. In analogy to what was observed for the β-alkyl substituted sapphyrins, H-type aggregates were seen for the water solubilized meso-substituted system in aqueous media. However, in contrast to the H-type dimers seen in the case of the meso-free systems in methanol, J-type dimers were observed in the case of the sapphyrins bearing two meso substituents in this solvent. The effective dimerization constants of several of the meso-diaryl sapphyrins were determined in methanol as were their pKa values in aqueous media. The solid state structure of the bis HBr salt of one of the meso-diaryl sapphyrins, specifically 10,15-bis(3,5-di-tert-butylphenyl)-3,22-diethyl-2,23-dimethylsapphyrin, was also determined and found to show elements in common with those of previously reported sapphyrin derivatives. In particular, the two counter Anions were found to be hydrogen bound above and below the diprotonated sapphyrin plane.
Ruyu Wang - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of a host–guest complex of the tris-urea receptor, 3-(4-nitrophenyl)-1,1-bis{2-[3-(4-nitrophenyl)ureido]ethyl}urea, that encapsulates hydrogen-bonded chains of dihydrogen Phosphate Anions with separate tetra-n-butylammonium
Acta Crystallographica Section E: Crystallographic Communications, 2019Co-Authors: Ruyu Wang, Shoujian Li, Chao HuangAbstract:The title compound, C25H25N9O9·C16H36N+·H2PO4− (I) or (C25H25N9O9)·(n-Bu4N+)·(H2PO4−) (systematic name: 3-(4-nitrophenyl)-1,1-bis{2-[3-(4-nitrophenyl)ureido]ethyl}urea tetrabutylammonium dihydrogen Phosphate), comprises a tris-urea receptor (R), a dihydrogen Phosphate Anion and a tetra-n-butylammonium cation. It crystallizes with two independent formula units in the asymmetric unit. The conformations of the two tris-urea receptors are stabilized by N—H⋯O and C—H⋯O intramolecular hydrogen bonds. Each dihydrogen Phosphate Anion has two O—H⋯O intermolecular hydrogen-bonding interactions with the other dihydrogen Phosphate Anion. Inversion-related di-Anion units are linked by further O—H⋯O hydrogen bonds, forming a chain propagating along the a-axis direction. Each dihydrogen Phosphate Anion makes a total of four N—H⋯O(H2PO4−) hydrogen bonds with two ureido subunits from two different tris-urea receptors, hence each tris-urea receptor provides the two ureido subunits for the encapsulation of the H2PO4− hydrogen-bonded chain. There are numerous intermolecular C—H⋯O hydrogen bonds present involving both receptor molecules and the tetra-n-butylammonium cations, so forming a supramolecular three-dimensional structure. One of the butyl groups and one of the nitro groups are disordered over two positions of equal occupancy.
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Crystal structure of a host-guest complex of the tris-urea receptor, 3-(4-nitro-phen-yl)-1,1-bis-{2-[3-(4-nitro-phen-yl)ureido]eth-yl}urea, that encapsulates hydrogen-bonded chains of di-hydrogen Phosphate Anions with separate tetra-n-butyl-ammonium
Acta crystallographica. Section E Crystallographic communications, 2019Co-Authors: Ruyu Wang, Shoujian Li, Chao HuangAbstract:The title compound, C25H25N9O9·C16H36N+·H2PO4 - (I) or (C25H25N9O9)·(n-Bu4N+)·(H2PO4 -) (systematic name: 3-(4-nitro-phen-yl)-1,1-bis-{2-[3-(4-nitro-phen-yl)ureido]eth-yl}urea tetra-butyl-ammonium di-hydrogen Phosphate), comprises a tris-urea receptor (R), a di-hydrogen Phosphate Anion and a tetra-n-butyl-ammonium cation. It crystallizes with two independent formula units in the asymmetric unit. The conformations of the two tris-urea receptors are stabilized by N-H⋯O and C-H⋯O intra-molecular hydrogen bonds. Each di-hydrogen Phosphate Anion has two O-H⋯O inter-molecular hydrogen-bonding inter-actions with the other di-hydrogen Phosphate Anion. Inversion-related di-Anion units are linked by further O-H⋯O hydrogen bonds, forming a chain propagating along the a-axis direction. Each di-hydrogen Phosphate Anion makes a total of four N-H⋯O(H2PO4 -) hydrogen bonds with two ureido subunits from two different tris-urea receptors, hence each tris-urea receptor provides the two ureido subunits for the encapsulation of the H2PO4 - hydrogen-bonded chain. There are numerous inter-molecular C-H⋯O hydrogen bonds present involving both receptor mol-ecules and the tetra-n-butyl-ammonium cations, so forming a supra-molecular three-dimensional structure. One of the butyl groups and one of the nitro groups are disordered over two positions of equal occupancy.
Youdou Zheng - One of the best experts on this subject based on the ideXlab platform.
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highly selective and sensitive Phosphate Anion sensors based on algan gan high electron mobility transistors functionalized by ion imprinted polymer
Scientific Reports, 2016Co-Authors: Dunjun Chen, Hai Lu, Rong Zhang, Youdou ZhengAbstract:A novel ion-imprinted electrochemical sensor based on AlGaN/GaN high electron mobility transistors (HEMTs) was developed to detect trace amounts of Phosphate Anion. This sensor combined the advantages of the ion sensitivity of AlGaN/GaN HEMTs and specific recognition of ion imprinted polymers. The current response showed that the fabricated sensor is highly sensitive and selective to Phosphate Anions. The current change exhibited approximate linear dependence for Phosphate concentration from 0.02 mg L−1 to 2 mg L−1, the sensitivity and detection limit of the sensor is 3.191 μA/mg L−1 and 1.97 μg L−1, respectively. The results indicated that this AlGaN/GaN HEMT-based electrochemical sensor has the potential applications on Phosphate Anion detection.
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Highly selective and sensitive Phosphate Anion sensors based on AlGaN/GaN high electron mobility transistors functionalized by ion imprinted polymer
Scientific Reports, 2016Co-Authors: Dunjun Chen, Hai Lu, Rong Zhang, Youdou ZhengAbstract:A novel ion-imprinted electrochemical sensor based on AlGaN/GaN high electron mobility transistors (HEMTs) was developed to detect trace amounts of Phosphate Anion. This sensor combined the advantages of the ion sensitivity of AlGaN/GaN HEMTs and specific recognition of ion imprinted polymers. The current response showed that the fabricated sensor is highly sensitive and selective to Phosphate Anions. The current change exhibited approximate linear dependence for Phosphate concentration from 0.02 mg L−1 to 2 mg L−1, the sensitivity and detection limit of the sensor is 3.191 μA/mg L−1 and 1.97 μg L−1, respectively. The results indicated that this AlGaN/GaN HEMT-based electrochemical sensor has the potential applications on Phosphate Anion detection.
Vincent M Lynch - One of the best experts on this subject based on the ideXlab platform.
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non cyclic formylated dipyrromethanes as Phosphate Anion receptors
Chemical Science, 2016Co-Authors: Murat K Deliomeroglu, Vincent M Lynch, Jonathan L SesslerAbstract:New tetrakis- and hexakis(1H-pyrrole-2-carbaldehyde) Anion receptors are described. The Anion binding properties of these receptors were studied in organic media and in the solid state. The receptors displayed good affinity for the dihydrogenPhosphate and pyroPhosphate Anions (as the tetrabutylammonium salts) in chloroform even in the presence of a polar protic solvent, methanol. Solution phase spectroscopic analyses proved consistent with the binding mode seen in single crystal structural studies of the dihydrogenPhosphate and pyroPhosphate complexes and provided support for the contention that these receptors undergo conformational reorganization in order to accommodate the bound oxoAnions both in chloroform solution and in the solid state.
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diindolylquinoxalines effective indole based receptors for Phosphate Anion
Journal of the American Chemical Society, 2006Co-Authors: Jonathan L Sessler, Vincent M LynchAbstract:The synthesis of a new series of 2,3-diindol-3‘yl quinoxalines (DIQ), as well as a comparison of their Anion recognition properties to those of our previously reported pyrrole based sensors, 2,3-dipyrrol-2‘yl quinoxalines, is reported. To the best of our knowledge, this new DIQ system represents the first example of a free-standing indole-based small molecule receptor for which evidence of Anion binding is available both in solution and in the solid-state. It also provides one of the few structurally characterized neutral receptor−dihydrogen Phosphate complexes. This work thus serves to demonstrate the utility of indoles as an Anion recognition motif.
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water soluble sapphyrins potential fluorescent Phosphate Anion sensors
Organic and Biomolecular Chemistry, 2003Co-Authors: Jonathan L Sessler, Julian M Davis, Vladimir Kral, Thomas Kimbrough, Vincent M LynchAbstract:As part of an ongoing effort to study the Anion binding properties of sapphyrins in various media, a number of previously reported water solubilized sapphyrins were studied in methanol and in buffered, neutral aqueous solutions and found to undergo self-aggregation under these solution phase conditions. The nature of the species produced as the result of self-aggregation and the processes leading to their formation were studied via UV-vis absorbance and fluorescence spectroscopy. In previous work (V. Kral, H. Furuta, K. Shreder, V. Lynch, and J. L. Sessler, J. Am. Chem. Soc., 1996, 118, 1595–1607.) it was found that the addition of Phosphate-type Anions to water soluble sapphyrins at pH 6.1 gives rise to visible spectroscopic changes consistent with the binding to the aggregated form and the concurrent formation of an Anion-bound dimer with effective equilibrium constants on the order of 100–300 M−1. In this study we show that at high Phosphate-to-sapphyrin ratios in neutral, buffered aqueous solutions further deaggregation occurs to produce an Anion-bound monomeric form. This highly fluorescent species is formed with effective equilibrium constants on the order of 6–19 M−1 leading to considerations that sapphyrins could function as fluorescent Phosphate Anion sensors. In an effort to modulate the deaggregation properties, several new sapphyrin derivatives bearing two meso aryl substituents were prepared and studied. The aggregation properties of these latter systems were analyzed in methanol and, in the case of one water solublized system, in neutral aqueous media. In analogy to what was observed for the β-alkyl substituted sapphyrins, H-type aggregates were seen for the water solubilized meso-substituted system in aqueous media. However, in contrast to the H-type dimers seen in the case of the meso-free systems in methanol, J-type dimers were observed in the case of the sapphyrins bearing two meso substituents in this solvent. The effective dimerization constants of several of the meso-diaryl sapphyrins were determined in methanol as were their pKa values in aqueous media. The solid state structure of the bis HBr salt of one of the meso-diaryl sapphyrins, specifically 10,15-bis(3,5-di-tert-butylphenyl)-3,22-diethyl-2,23-dimethylsapphyrin, was also determined and found to show elements in common with those of previously reported sapphyrin derivatives. In particular, the two counter Anions were found to be hydrogen bound above and below the diprotonated sapphyrin plane.