Information AboutNon-coordinating Anion |
| CATEGORIES ABOUT NON-COORDINATING ANION | |
| coordination chemistry | |
| anions | |
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They are useful because they generally do not interfere with the reactions at the cation. Some examples of weakly-coordinating anions are BF4- and PF6-. ClO4- has almost fallen out of use due to safety concerns and it restricted to applications where fluoride abstraction is a problem. A revolution in this area occurred several years ago with the use of B commonly abbreviated as [BArF4 -, or "BARF", which is far less coordinating than the others mentioned above. Non-coordinating anions have the Electron Density symmetrically spread out over several Electronegative atoms. Because of its size, BARF is particularly non-coordinating. In contrast, metal ions, such as Zr(IV) can abstract Fluoride from the BF4- and PF6- anions. The weakly-coordinating ClO4- anion is a potent if inert Oxidizer , making it potentially Explosive if there are species that can be readily oxidized near it. Another advantage of BARF Salts is that they are Soluble in Non-polar Organic Solvent s; Polar Solvent s also tend to bind to metal cations, which can diminish their Affinity for weakly-coordinating Substrate s such as the examples here. BARF salts have been used to Catalyze Olefin Hydrogenation , Hydrosilation , Oligomerization , and the Living Polymerization of Ethylene . REFERENCES
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