Fluoroacid–base reactions of a room-temperature ionic liquid, 1-ethyl-3-methylimidazolium fluorohydrogenate (EMIm(HF)2.3F, EMIm = 1-ethyl-3-methylimidazolium cation), and Lewis fluoroacids (BF3, PF5, AsF5, NbF5, TaF5 and WF6) give EMIm salts of the corresponding fluorocomplex anions, EMImBF4, EMImPF6, EMImAsF6, EMImNbF6, EMImTaF6 and EMImWF7, respectively. Attempts to prepare EMImVF6 by both the acid–base reaction of EMIm(HF)2.3F with VF5 and the metathesis of EMImCl with KVF6 failed due to the strong oxidizing power of the pentavalent vanadium, whereas EMImSbF6 was successfully prepared only by the metathesis of EMImCl and KSbF6. EMImBF4, EMImSbF6, EMImNbF6, EMImTaF6 and EMImWF7 are liquids at room temperature whereas EMImPF6 and EMImAsF6 melts at around 330 K. Raman spectra of the obtained salts showed the existence of the EMIm cation and corresponding fluorocomplex anions. IR spectroscopy revealed that strong hydrogen bonds are not observed in these salts. EMImAsF6
(mp 326 K) and EMImSbF6
(mp 283 K) are isostructural with the previously reported EMImPF6. The melting point of the hexafluorocomplex EMIm salt decreases with the increase of the size of the anion (PF6− < AsF6− < SbF6−
常温
离子液体1-乙基-3-甲基
咪唑鎓
氟氢酸盐(
EMIm(HF)2.3F,
EMIm = 1-乙基-3-甲基
咪唑鎓阳离子)与路易斯
氟酸(
BF3、PF5、
AsF5、NbF5、TaF5和WF6)发生
氟酸-碱反应,分别生成相应的
氟配合阴离子的
EMIm盐:
EMImBF4、
EMImPF6、
EMImAsF6、
EMImNbF6、
EMImTaF6和
EMImWF7。尝试通过
EMIm(HF)2.3F与VF5的酸碱反应以及
EMImCl与KVF6的交换反应制备
EMImVF6因五价
钒的强氧化性而失败,而
EMImSbF6仅通过
EMImCl与KSbF6的交换反应成功制备。
EMImBF4、
EMImSbF6、
EMImNbF6、
EMImTaF6和
EMImWF7在常温下为液体,而
EMImPF6和
EMImAsF6的熔点在约330 K。所获得盐的拉曼光谱显示存在
EMIm阳离子及相应的
氟配合阴离子。红外光谱揭示这些盐中未观察到强氢键。
EMImAsF6(熔点326 K)和
EMImSbF6(熔点283 K)与之前报道的
EMImPF6同构。六
氟配合物
EMIm盐的熔点随阴离子尺寸的增加而降低(PF6− < AsF6− < SbF6− < NbF6− ≈ TaF6−)。
[Li(XeF<sub>2</sub>)<sub><i>n</i></sub>](AF<sub>6</sub>) (A = P, As, Ru, Ir), the First Xenon(II) Compounds of Lithium. Synthesis, Raman Spectrum, and Crystal Structure of [Li(XeF<sub>2</sub>)<sub>3</sub>](AsF<sub>6</sub>)
作者:Gašper Tavčar、Boris Žemva
DOI:10.1021/ic302323j
日期:2013.4.15
alkali metal; A = P, As, V, Ru, Ir, Sb, Nb, Ta) and xenon difluoride were studied in anhydrous hydrogen fluoride solvent. The coordination products [M(XeF2)n]AsF6 were only observed in the case of LiAF6 (A = P, As, Ru, Ir), and the crystal structure of [Li(XeF2)3]AsF6 was determined (monoclinic space group P21 with a = 6.901(9) Å, b = 13.19(2) Å, c = 6.91(1) Å, β = 91.84(2)°, and Z = 2). The coordination
在无
水氟化氢溶剂中研究了MAF 6型化合物(M =碱
金属; A = P,As,V,Ru,Ir,Sb,Nb,Ta)与二
氟化
氙之间的反应。仅在LiAF 6(A = P,As,Ru,Ir)的情况下观察到配位产物[M(XeF 2)n ] AsF 6,[Li(XeF 2)3 ] AsF 6的晶体结构为确定的(单斜空间群P 2 1,a = 6.901(9)Å,b = 13.19(2)Å,c = 6.91(1)Å,β= 91.84(2)°,Z= 2)。
锂的配位球由六个F原子组成。该化合物系列还通过拉曼光谱法表征。