Microscopic study of binary mixtures between pyrrolidinium bis(triflorosulfonyl)imide and dimethyl sulfoxide/acetonitrile
Microscopic study of binary mixtures between pyrrolidinium bis(triflorosulfonyl)imide and dimethyl sulfoxide/acetonitrile
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吡咯烷鎓双(三氟磺酰基)亚胺与二甲亚砜/乙腈二元混合物的显微研究
DOI：
10.1007/s11426-016-5583-2
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Yu Zhi-Wu
中科院分区：
文献类型：
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作者：
Ashraf Hamad;Zhou Yu;Xu Jing;Ahmad Khalil;Yu Zhi-Wu
本工作分析了代表性的吡咯烷基离子液体1-丁基-1-甲基-吡咯烷双（三氟磺酰基）-酰亚胺（[BMPyrr][TFSI]）与二甲基亚砜（DMSO）和乙腈（AN）的分子相互作用。衰减全反射傅里叶变换红外光谱（ATR-FTIR）和密度泛函理论（DFT）计算中使用的调查，而过量红外光谱和二维相关光谱用于探索数据的详细。研究发现，分子溶剂能与TFSI-（主要与S=O，弱与S-N-S基团）相互作用。与DMSO的强相互作用相比，AN与BMPyrr+的相互作用微弱。相互作用的强度取决于溶剂的给电子能力。混合后，阳离子中的C-Hs和阴离子中的S-N-S之间的氢键减弱，而阴离子中的S=O之间的氢键增强。在与阳离子N直接连接的C-H中，C1-H是DMSO和AN的主要相互作用位点。这意味着C1−H是吡咯烷鎓阳离子中酸性最强的氢。
Molecular interactions of a representative pyrrolidinium-based ionic liquid 1-butyl-1-methyl-pyrrolidinium bis(triflorosulfonyl)- imide ([BMPyrr][TFSI]) with dimethyl sulfoxide (DMSO) and acetonitrile (AN) have been analyzed in this work. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and density functional theory (DFT) calculations are used in the investigation, while excess infrared spectra and two-dimensional correlation spectroscopy are used to explore the data in detail. It has been found that the molecular solvents can interact with TFSI- (mainly with S=O and weakly with S–N–S group). AN interacts feebly with BMPyrr+ as compared with the strong interaction of DMSO. The strength of the interactions depends on the electron donating ability of the solvent. Upon mixing, hydrogen bonds regarding C−Hs in cation and S–N–S in anion are weakened, while that regarding S=O in anion is strengthened. Among the C−Hs which are connected directly with the N of the cation, C1−H is the main interaction site for both DMSO and AN. This means that C1−H is the most acidic hydrogen in pyrrolidinium cation.