对1,2-di-tert-butoxyethane的整合性研究,特别关注左侧氧气效应
Hidemine Furuya1, Takahiro Takekiyo2, Ryoichi Wada3
1School of Materials and Chemical Technology, Institute of Science Tokyo, 2-12-1-S8-29 Ookayama, Meguro-ku, Tokyo 152-8550, Japan. furuya@mct.isct.ac.jp.
Physical chemistry chemical physics : PCCP
|March 4, 2026
概括
尽管有预期,但1,2-di-tert-butoxyethane (DTBE) 上的大型三基组并没有显著改变中央C-C键的左边偏好. 这项研究揭示了乙烯糖醇单元中的 gauche 氧气效应不仅仅依赖于通过空间接触.
科学领域:
- 物理化学 物理化学
- 分子光谱学 分子光谱学
- 计算化学的计算化学
背景情况:
- 聚氧乙烯衍生物是重要的工业化学品,因为它们的可溶性和由乙烯基醇 (EG) 单位所赋予的独特特性.
- 1,2-二次氧乙 (DME) 作为研究EG单位特性,特别是左侧氧效应的模型化合物.
- 了解终端组置换如何影响分子构造和相互作用对材料科学至关重要.
研究的目的:
- 为了研究大型,非极性三丁基对1,2-di-tert-butoxyethane (DTBE) 的构造性行为的影响.
- 阐明DTBE中穿越空间1,5相互作用和左侧氧气效应的作用.
- 为了比较DTBE与DME在不同阶段和溶剂环境中的形状偏好.
主要方法:
- 通过拉曼光谱学对DTBE进行符合性分析.
- 通过核磁共振 (NMR) 光谱学获得的补充数据.
- 通过量子化学计算提供的验证和理论见解.
主要成果:
- 尽管存在疏水性三丁基,但DTBE在水中具有可溶性,这表明了复杂的溶解效应.
- 虽然终端债券旋转受到限制,但中央C-C债券保留了相当大的左边偏好,类似于DME.
- 在气相中观察到通过空间的1,5-tert-butyl-oxygen接触,但在凝结相中被抑制,这表明了相位依赖的相互作用.
结论:
- 乙烯糖醇单元中的左侧氧效应不仅仅由涉及相邻的C-O键的透空间1.5接触决定.
- 静电相互作用在非键介质中很重要,而键在原性溶剂中占主导地位.
- 终端组的体积对中央C-C债券在DTBE与DME相比的左边偏好影响有限.
更多相关视频
相关概念视频
02:18Conformations of Ethane and Propane
In an organic molecule, free rotation about the carbon-carbon single bond results in energetically different conformers of the molecule. Due to this rotation, called the internal rotation, ethane has two major conformations — staggered and eclipsed.
Staggered conformation is a low energy and more stable conformation with the C-H bonds on the front carbon placed at 60°dihedral angles relative to the C-H bonds on the back carbon, leading to a reduced torsional strain. In staggered ethane, the...
Staggered conformation is a low energy and more stable conformation with the C-H bonds on the front carbon placed at 60°dihedral angles relative to the C-H bonds on the back carbon, leading to a reduced torsional strain. In staggered ethane, the...
02:20Conformations of Butane
Unlike ethane and propane that have only two major conformations, butane has more than two conformers. The staggered form of butane in which the bulky methyl groups on the two carbons are placed on opposite sides, that is, at a dihedral angle of 180°, is the lowest energy, most stable form — called the anti conformer. This conformation is stabilized due to the absence of steric repulsion between the largely spaced out methyl groups. The other two staggered conformations are degenerate and have...
02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
03:08Hydroboration-Oxidation of Alkenes
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
02:36Regioselectivity and Stereochemistry of Hydroboration
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
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.