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Updated: Mar 27, 2026
A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
An Aliphatic Solvent-Soluble Lithium Salt of the Perhalogenated Weakly Coordinating Anion [Al(OC(CCl3)(CF3)2)4](-)
Xin Zheng1, Zaichao Zhang2, Gengwen Tan1
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University , Nanjing 210093, P. R. China.
Abstract:
The facile synthesis of a new highly aliphatic solvent-soluble Li(+) salt of the perhalogenated weakly coordinating anion [Al(OC(CCl3)(CF3)2)4](-) and its application in stabilizing the Ph3C(+) cation were investigated. The lithium salt Li[Al(OC(CCl3)(CF3)2)4] (4) was prepared by the treatment of 4 mol equiv of HOC(CCl3)(CF3)2 with purified LiAlH4 in n-hexane from -20 °C to room temperature. Compound 4 is highly soluble in both polar and nonpolar solvents, and it bears both CCl3 and CF3 groups, resulting in a lower symmetry around the Al center compared to that of Li[Al(OC(CF3)3)4] (1). Treatment of 4 with Ph3CCl afforded the ionic compound [Ph3C][Al(OC(CCl3)(CF3)2)4] (5) bearing the Ph3C(+) cation with concomitant elimination of LiCl, suggesting the potential application of [Al(OC(CCl3)(CF3)2)4](-) in stabilizing reactive cationic species. Compounds 4 and 5 were fully characterized by spectroscopic and structural methods.
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