氧化物替代的林德奎斯特 (MW5) 和凯金 (Keggin) 聚氧甲酸盐的质子解和凝结反应:比较实验和建模研究
Daniel Lebbie1, Thompson Izuagie1, Magda Pascual-Borràs1
1NUPOM Lab, Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K.
Inorganic chemistry
|January 29, 2025
概括
金属氧化物中的质子转移是反应性的关键. 这项研究研究了Ti和Sn聚氧甲酸盐,发现Sn更容易发生质溶解,并揭示了溶剂对水解和凝结反应的影响.
科学领域:
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
背景情况:
- 在金属氧化物表面的质子转移和迁移对于理解化学反应,包括质子和水相互作用至关重要.
- 分子金属氧化物,如多氧甲酸盐 (POM) 和金属氧化物,作为研究这些表面现象的模型系统.
研究的目的:
- 研究氧化物Ti和Sn替代的林德奎斯特和凯金多氧金属酸盐 (POMs) 的水解和凝结反应.
- 阐明这些分子金属氧化物系统中质子转移和迁移的机制.
- 了解原子 (Ti与Sn),POM结构 (Lindqvist与Keggin) 和溶剂对反应路径和速率的影响.
主要方法:
- 溶液核磁共振 (NMR) 光谱法用于研究水解和凝结反应.
- 分析了动力实验,以量化比较反应平衡和速率.
- 进行密度函数理论 (DFT) 计算,以确定比较的能量和反应概况.
主要成果:
- 与其类同类 (Ti-POMs) 相比,替代POMs (Sn-POMs) 对质溶解的敏感性显著更高.
- 涉及Lindqvist {MW5} 离子的反应通常比Keggin {MPW11} 离子的反应快.
- 氧化衍生物的凝结对于Ti-POMs来说更容易,溶剂DMSO在所有研究的POMs中抑制了凝结.
结论:
- 该研究提供了对分子金属氧化物系统内的质子转移反应的详细见解.
- 反应结果取决于异构原子的性质,POM结构和溶剂极性.
- 这些发现有助于对金属氧化物水解/凝结和金属氧化物表面反应的基本理解.
相关概念视频
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
10.8K
Alkenes can be dihydroxylated using potassium permanganate. The method encompasses the reaction of an alkene with a cold, dilute solution of potassium permanganate under basic conditions to form a cis-diol along with a brown precipitate of manganese dioxide.
10.8K
Aldol Condensation with β-Diesters: Knoevenagel Condensation
2.9K
The Knoevenagel condensation is an aldol-type reaction involving the condensation of aldehydes or ketones with active methylene compounds such as β-diesters to produce substituted olefins.
2.9K
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
9.8K
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
9.8K
α-Alkylation of Ketones via Enolate Ions
3.0K
Ketones with α protons are deprotonated by strong bases like lithium diisopropylamide (LDA) to form enolate ions. The anion is stabilized by resonance, and its hybrid structure exhibits negative charges on the carbonyl oxygen and the α carbon. This ambident nucleophile can attack an electrophile via two possible sites: the carbonyl oxygen, known as O-attack, or the α carbon, known as C-attack. The nucleophilic attack via the carbanionic site is preferred. This is due to the...
3.0K
Oxidative Cleavage of Alkenes: Ozonolysis
9.9K
In ozonolysis, ozone is used to cleave a carbon–carbon double bond to form aldehydes and ketones, or carboxylic acids, depending on the work-up.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
9.9K
Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
5.6K
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
5.6K


