在阴离子二氧化 () 氧化二酸中产生结和共振稳定效应
Rebecca L Jones1, Louis J Morris1, Clement G Collins Rice1
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK. dermot.ohare@chem.ox.ac.uk.
Physical chemistry chemical physics : PCCP
|May 30, 2023
概括
这项研究详细介绍了一种新型氧化二酸的合成. 这种独特的阴离子采用了一种不寻常的复合体形式,通过电子移位和键稳定,为化学稳定提供了洞察力.
科学领域:
- 协调化学 协调化学
- 超分子化学 超分子化学
- 有机合成 有机合成
背景情况:
- 双氨基联体是协调化学中的多功能前体.
- 对于设计新的化学系统来说,了解质子联体的分体平衡是至关重要的.
- 化合物的质子化可以导致各种结构动图.
研究的目的:
- 为了合成和表征一种新的bis () 氧化二氧化酸离子.
- 为了研究异常 tautomeric 形式采用了阴.
- 量化这个复合体的能量稳定,并确定有助于的因素.
主要方法:
- 通过质子化合成双 () 氧化二氧化酸离子.
- 使用NMR和IR光谱学的完整表征.
- 通过X射线晶体学进行结构阐明.
- 计算分析包括能源计算和拓分析.
主要成果:
- 成功合成了二氧化二酸离子[H2L][BF4]和[H2L][H2N{B(C6F5) 3}2]的两个不同的盐.
- 鉴定了一种不寻常的[HNONH]+轮体形式,其稳定由电子移位和N+HO-键.
- 能量分析显示,与替代品相比,观察到的复合体具有显著的稳定性 (22.6 和 263.1 kJ mol-1).
- 估计不同溶剂中的pKa值 (4.2在THF中和11.4在乙酸中).
结论:
- 双氧化二酸离子存在于一种独特的,高度稳定的复合体形式.
- 电子脱离氧气和静电结合的移位起到了稳定这种结构的关键作用.
- 这项研究提供了关于双氨基系统的质子化行为和复合体的宝贵数据.
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