Superweak anion

Figure 4 New cationic complexes isolated with the 1-Et-CBnFif superweak anion...

Monocarborane monoanions, especially derivatives of CBuHn", are among the best superweak anions available today.They are extremely weakly coordinating and possess extraordinary chemical, electrochemical, and thermal stability. Important examples include 7,8,9,10,1 1,12-CB H6X6 (abbreviated CB H6X6 X = Cl, Br, and I ), 1-Me-... 

The SbFg anion was one of the first examples of a weakly coordinating anion (WCA) or superweak anion, an anion so unreactive as to coexist in a salt with a simple, highly reactive carbocation. Chemists could scarcely believe this feat had been accomplished. Olah realized that carbocations such as r-butyl may also reversibly eliminate H to form alkenes ... 

B. G. Nolan, S. Tsujioka, S. H. Strauss, in Ruorinated Materials for Eneigy Conversion, Chap. 9 (T. Nakajrma, H. Groult, Eds.), Elsevier, New York, 2005. Electrochemical properties ofUtMum electrolytes based on bis(poly fluorodiolato)borate tind tetrakis(poly fluoroalkoxy) aluminate superweak anions. 

S. Tsujioka, B. G. Nolan, H. Takase, B. P. Pauber, S. H. Strauss, J. Electrochem. Soc. 2004, 151, A1418-A1423. Conductivities and electrochemical stabilities of lithium salts of polyfluo-roalkoxyaluminate superweak anions. 

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