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The first 1-alkyl-3-perfluoroalkyl-4,5- dimethyl-1,2,4-triazolium salts
Hong Xue1, Brendan Twamley, Jean'ne M Shreeve
1Department of Chemistry, University of Idaho, Moscow, Idaho 83843-2343, USA.
Abstract:
Syntheses of quaternary 1-alkyl-3-perfluoroalkyl-4,5-dimethyl-1,2,4-triazolium iodides have led to a variety of new quaternary salts via metathesis reactions. 1,4,5-Trimethyl-3-trifluoro-methyl-1,2,4-triazolium iodide (6) with LiN(SO(2)CF(3))(2), KSO(3)CF(3), AgClO(4), AgBF(4); 1-(3-fluoropropyl)-3-trifluoromethyl-4,5-dimethyl-1,2,4-triazolium iodide (7) with LiN(SO(2)CF(3))(2); and 1,4,5-trimethyl-3-perfluorooctyl-1,2,4-triazolium iodide (8) with LiN(SO(2)CF(3))(2), AgClO(4), AgBF(4) gave excellent yields of new thermally stable and relatively low melting quaternary salts. The structure of 1,4,5-trimethyl-3-perfluorooctyl-1,2,4-triazolium tetrafluoroborate (11c) was confirmed by single-crystal X-ray analysis. Although the molecular weight of 11c (cation) is 3-fold greater than that of the 3-trifluoromethyl derivative 9d, its melting point is 32 degrees C lower.
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