Bond Formation Studies By Charge Density Measurements and Solid State 17O NMR Spectrometry

通过电荷密度测量和固态 17O NMR 光谱法研究键形成

• 批准号: EP/E018203/1
• 负责人: John Wallis
• 金额: $ 42.35万
• 依托单位: Nottingham Trent University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FE018203%2F1
• 关键词: Bond; Formation; Studies; Charge; Density

This project concerns the formation of chemical bonds. The reactions chosen are addition reactions of electron-rich groups such as amines or those containing negatively charged oxygen atoms with electron-poor groups such as carbon-carbon double bonds which have electron attracting groups attached. Molecules will be prepared which have a pair of such groups held in close proximity. The degree of bond formation between them will be detected by measurements of the electron density between them, and by nuclear magnetic resonances (NMR) measurements on powdered crystalline samples - detecting either the nitrogen (as 15N) or oxygen (as 17O) atom of the electron-rich group. These measurements are at the cutting edge of both these techniques. The electron density distribution on a particular molecule is determined from very accurate X-ray diffraction measurements (XRD) on a small crystal, and this will contribute to the growing use of this technique internationally to examine weak bonding interactions. Of particular importance is to determine how the properties of the electron density distribution between the reacting groups changes as the distance between the groups decreases i.e. as the bond forms. Use of NMR measurements on powdered crystalline samples means that the solid state structure determined by X-ray diffraction, can be directly related to the position of the signal from N or O in the NMR experiment. The NMR measurements using 17O will be ground breaking, since this has only become feasible through recent developments of the technique, including double rotation of the sample in the magnetic field. Nevertheless, for the 17O measurements it will be necessary to prepare compounds which are enriched in the 17O isotope. Finally, and of particular importance, the choice of cation accompanying the oxygen anion will be varied to determine how this alters the reactivity of the oxygen anion, which will be monitored by structural (XRD) and NMR measurements building on earlier results. The reactivity of the oxygen would be expected to be decreased by cations which bind more tightly to it, and our measurements will provide an approach to quantify this.

该项目涉及化学债券的形成。选择的反应是富含电子基团的添加反应，例如胺或含有带负电的氧原子的氨基含量基团，例如碳碳双键，这些碳碳双键具有具有电子吸引基团的基团。将制备分子，该分子在近距离近距离固定。通过测量它们之间的电子密度，以及通过对粉末状结晶样品的测量值（NMR）测量 - 检测氮（AS 15N）或氧气（AS 17O）原子，通过测量它们之间的键形成程度。这些测量在这两种技术的最前沿。特定分子上的电子密度分布是由非常精确的X射线衍射测量（XRD）确定的，这将有助于国际上这种技术的日益增长的使用，以检查弱键合相互作用。特别重要的是确定反应组之间电子密度分布的性能如何随着组之间的距离降低，即键形式。在粉末状结晶样品上使用NMR测量结果是指由X射线衍射确定的固态结构可以直接与NMR实验中N或O的信号位置有关。使用17O的NMR测量将是突破性的，因为这仅通过该技术的最新发展才能可行，包括磁场中样品的双重旋转。然而，对于17o测量值，有必要制备富含17o同位素的化合物。最后，尤其重要的是，伴随氧阴离子的阳离子的选择将有所不同，以确定这如何改变氧阴离子的反应性，氧阴离子将通过结构（XRD）和NMR测量值对早期结果进行监测。预计氧气的反应性将通过更紧密地与之结合的阳离子降低，我们的测量结果将提供一种量化这一点的方法。

项目成果

O - vs. N -protonation of 1-dimethylaminonaphthalene-8-ketones: formation of a peri N-C bond or a hydrogen bond to the pi-electron density of a carbonyl group

1-二甲基氨基萘-8-酮的 O - 与 N - 质子化：与羰基的π电子密度形成近N-C键或氢键

• DOI: 10.1039/c4ce00981a
• 发表时间: 2014
• 期刊: CrystEngComm
• 影响因子: 3.1
• 作者: Mercadal N

A multinuclear solid state NMR, density functional theory and X-Ray diffraction study of hydrogen bonding in Group I hydrogen dibenzoates

I 族二苯甲酸氢盐中氢键的多核固态 NMR、密度泛函理论和 X 射线衍射研究

• DOI: 10.1039/c3ce41258j
• 发表时间: 2013
• 期刊: CrystEngComm
• 影响因子: 3.1
• 作者: Rees G

Mapping of N-C Bond Formation from a Series of Crystalline Peri-Substituted Naphthalenes by Charge Density and Solid-State NMR Methodologies

通过电荷密度和固态 NMR 方法绘制一系列结晶邻位取代萘的 N-C 键形成图

• DOI: 10.1002/ange.202111100
• 发表时间: 2021
• 期刊: Angewandte Chemie
• 作者: Rees G

Mapping of N-C Bond Formation from a Series of Crystalline Peri-Substituted Naphthalenes by Charge Density and Solid-State NMR Methodologies.

• DOI: 10.1002/anie.202111100
• 发表时间: 2021-10-25
• 期刊: Angewandte Chemie (International ed. in English)
• 作者: Rees GJ;Pitak MB;Lari A;Day SP;Yates JR;Gierth P;Barnsley K;Smith ME;Coles SJ;Hanna JV;Wallis JD
• 通讯作者: Wallis JD

Measuring multiple 17O-13C J-couplings in naphthalaldehydic acid: a combined solid state NMR and density functional theory approach.

测量萘醛酸中的多个 17O-13C J 耦合：固态 NMR 和密度泛函理论相结合的方法。

• DOI: 10.1039/c9cp03977e
• 发表时间: 2020
• 期刊: PCCP
• 作者: Rees GJ