Boron-based anion receptors

X. Sun, H. S. Lee, X. Q. Yang, J. McBreen, J. Electrochem. Soc. 1999, 146, 3655-3659. Comparative studies of the electrochemictil and thermal stahUity of two types of composite lithium battery electrolytes using boron-based anion receptors. 

LiLF, Lee HS, LiH, YangXQ, Nam KW, Yoon WS, McBreen J, Huang XJ (2008) New electrolytes for lithium ion batteries using LiF salt and boron based anion receptors. J Power Sources 184 517-521... 

Lee HS, Yang XQ, Xiang CL, McBreen J (1998) The S3mthesis of a new family of boron-based anion receptors and the study of their effect on ion pair dissociation and conductivity of lithium salts in nonaqueous solutions. J Electrochem Soc 145 2813-2818. doi 10.1149/1.1838719... 

Sun X, Lee HS, Yang XQ, McBreen J (1999) Comparative studies of the electrochemical and thermal stability of two types of composite lithium battery electrol34es using boron-based anion receptors. J Electrochem Soc 146 3655-3659. doi 10.1149/1.1392529... 

Xie B, Lee HS, Li H, Yang XQ, McBreen J, Chen LQ (2008) New electrolytes using Li20 or Li202 oxides and tris(pentafluorophenyl)borane as boron based anion receptor for lithium batteries. Electrochem Commun 10 1195-1197. doi 10.1016/j.elecom.2008.05.043... 

Another concept for anion receptors comprises bases on boron. It is possible to obtain highly conducting liF solutions in nonaqueous solvents hy means of boron additives, such as tris(pentafluorophenyl)borane (TPFPB) (see Figure 17.15) [423, 424], Solubihty of LiF can be increased by 6 orders of magnitude up to 1 mol- solutions. This observation can be exclusively attributed to Equation 17.27 Moreover, 1 molL solutions of LiF and boron-based anion receptors show good electrochemical stabiHty up to 5 V vs Li. Therefore, full battery systems... 

Employing the cell Li(m)/LiMn204, the authors demonstrated extended cycling at 55°C at very near 100 % efficiency [51]. Information on the solubilities of these boron-based anion receptors at low temperatures has not yet been reported. 

Since these anion receptors based on boron offer a wide variety of merits, their application seems promising if the cost and toxicology do not constitute any serious barrier for industry-scale productions. 

Although technically a heteroelement rather than a metal, some interesting Lewis acidic receptors for anions have been based on boron-containing systems. The first evidence for this type of anion receptor was published in 1967, one of the earliest examples of anion binding. Compound 21, when compared with 22, exhibited a chelate effect in the binding of methoxide anions (3). 

Y. Terashima, M. Takayama, K. Isozaki, H. Maeda, Ion-based materials of boron-modified dipyrrolyldiketones as anion receptors. Chem. Commun. 49, 2506-2508 (2013)... 

Membranes and Molecular Assemblies The Synkinetic Approach 6 Calixarenes Revisited 7 Self-assembly in Supramolecular Systems 8 Anion Receptor Chemistry 9 Boronic Acids in Saccharide Recognition 10 Calixarenes An Introduction, 2nd Edition 11 Polymeric and Self Assembled Hydrogels From Fundamental Understanding to Applications 12 Molecular Logic-based Computation 13 Supramolecular Systems in Biomedical Fields 14 Synthetic Receptors for Biomolecules Design Principles and Applications... 

The electron-deficient nature of 3c <-> C1-TATA+ led to higher stability of electrons in the Col structure, resulting in relatively higher values of electron mobility. The properties and packing structures of ion-based assemblies can be modulated by further modifications of anion receptors as observed in semifluoroalkyl-substituted P-benzo- and P-coranulene-fused j and boron-modified derivatives. " ... 

Boron-containing compounds, especially those with only three substitutions, are mostly known for their functions as anion receptors. However, some of these compounds are also capable of forming an SEl, making them bi-functional additives [78]. The lithium salts with tetra-substituted boron anions such as LiBOB and LiDFOB can serve as SEI-forming additives in electrolytes based on other salts... 

Many of the receptors synthesised interact with a wide variety of anions however, selectivity has been introduced to these systems. Ferrocene-based systems have been shown to detect aqueous phosphate [99] and sulphate [100] ions. Ferrocene boronic acid has been shown to associate with fluoride ion with much stronger binding than to chloride,bromide and other anions [101]. 

Boronic acids RB(OH)2, boronic esters RB(OR)2, and triorganoboranes R3B have been studied extensively for the selective recognition of anions. " Moreover, arylboronic acids have proven highly useful for sensing of saccharides based on the facile formation of esters with diols, thus providing an excellent alternative to more commonly employed synthetic molecular receptors based on hydrogenbonding interactions. Absorption and fluorescence spectroscopy, circular dichroism, and cyclic voltammetry have all been successfiilly used as detection methods for organoboron sensors. 

The first literature example of a mercury based receptor (32) for anions was analogous to the chelating boron receptor discussed earlier. The crystal structure indicated that two molecules of Compound 32 asociate with one chloride ion, which sits in a four-coordinate binding site. Solution studies, however, gave results indicative of 1 l binding for halide anions (94, 95). This simple... 

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