Hydrogen Bonding Interactions in Three 2-Mercaptoethanol Systems: An Excess Infrared Spectroscopic Study
Hydrogen Bonding Interactions in Three 2-Mercaptoethanol Systems: An Excess Infrared Spectroscopic Study
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DOI：
10.1366/000370209790109049
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发表时间：
2009-12
影响因子：
3.5
通讯作者：
Nannan Wang;Qingzhong Li;Zhi‐Wu Yu
中科院分区：
文献类型：
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作者：
Nannan Wang;Qingzhong Li;Zhi‐Wu Yu
本文研究了具有代表性的2-巯基乙醇（ME）分子的氢键性质，其中OH和SH两个官能团被认为与质子接受分子竞争性或选择性地相互作用。采用过量红外吸收光谱法研究了ME-CCl_4、ME-二甲基亚砜（DMSO）和ME-丙酮三个二元体系。结果表明，当ME中加入DMSO或丙酮时，它们优先与OH形成氢键，且ME-DMSO体系中的氢键比ME-丙酮体系中的氢键强。当CCl 4加入到ME中时，随着CCl 4浓度的增加，涉及SH基团的弱氢键优先断裂。详细讨论了ME在惰性稀释剂CCl_4中的整个浓度范围内的离解过程。在很低的CCl 4浓度范围内，高度氢键ME多聚体主要破碎成中等大小的聚集体。三聚体和二聚体的量首先增加，然后在x（CCl 4）= 0.77时开始减少。这些结果表明，过量红外光谱可以提供详细的分子图像在含有复杂的氢键相互作用的液体溶液。它还可以帮助在重叠吸收带的去卷积中定位各个峰的位置。
The hydrogen bonding properties of a representative molecule, 2-mercaptoethanol (ME), of which two functional groups OH and SH are believed to interact competitively or selectively with proton-accepting molecules, have been studied. Three binary systems, namely ME–CCl4, ME–dimethyl sulfoxide (DMSO), and ME–acetone, were investigated with excess infrared absorption spectroscopy. It is found that when DMSO or acetone is added into ME, they preferentially form hydrogen bonds with OH, and the hydrogen bonds in the ME–DMSO system are stronger than those in the ME–acetone system. When CCl4 is added into ME, the weak hydrogen bonds involving the SH group are broken preferentially with increasing CCl4 concentration. The dissociation process of ME in the inert diluent CCl4 over the entire concentration range has been discussed in detail. In the very low concentration range of CCl4, the highly hydrogen bonded ME multimers mainly break into medium-sized aggregates. The amount of the trimers and dimers first increases and then, at x(CCl4) = 0.77, begins to decrease. These results suggest that excess infrared spectroscopy can provide detailed molecular pictures in liquid solutions containing complex hydrogen bonding interactions. It can also help to locate individual peak positions in the deconvolution of overlapped absorption bands.