nucleophilicity

简明释义

英[ˌnjuːkləˈfɪlɪsɪti]美[ˌnjuːkləˈfɪlɪsɪti]

n. [有化] 亲核性

英英释义

单词用法

同义词

反义词

例句

1.On the basis of equilibrated geometrical structure obtained by B3LYP/6-311G method, the nucleophilicity of-N(CH3)2 and-NH2 groups are investigated by electrostatic potential and MO calculations.

在B3LYP/6-311G计算所得的平衡几何构型基础上，分别根据静电势和分子轨道计算研究了分子中-NH2和-N（CH3）2的亲核性，并与偏二甲基肼和卤代烃反应的实验结果进行了对比分析。

2.On the basis of equilibrated geometrical structure obtained by B3LYP/6-311G method, the nucleophilicity of-N(CH3)2 and-NH2 groups are investigated by electrostatic potential and MO calculations.

在B3LYP/6-311G计算所得的平衡几何构型基础上，分别根据静电势和分子轨道计算研究了分子中-NH2和-N（CH3）2的亲核性，并与偏二甲基肼和卤代烃反应的实验结果进行了对比分析。

3.At the same time, discuss about the impact factor to nucleophilicity such as the number of attract electron group, ability of attract electron and the nucleophilic substitution reaction part.

并且对亲核试剂的体积效应、溶剂效应对亲核性影响，底物上吸电子基团的数目、吸电子能力对亲电性的影响，以及亲核取代反应的发生部位受哪些因素影响进行探讨。

4.In this paper, electroaffinity and nucleophilicity of organic compound have been investigated, and their application in organic synthesis also has been discussed.

从电性角度讨论了有机物分子的亲电性和亲核性问题，并阐述了两者在有机合成中的应用。

5.It compares the nucleophilicity of nocleophilic reagent with the similarities and differences of basicity.

把亲核剂的亲核性和碱性的区别与相同之处进行了比较。

6.The nucleophilicity of the hydroxide ion makes it a strong base in organic reactions.

氢氧根离子的亲核性使其在有机反应中成为强碱。

7.In comparing the nucleophilicity of different amines, we found that primary amines are generally more reactive.

在比较不同胺的亲核性时，我们发现初级胺通常更具反应性。

8.The solvent can significantly affect the nucleophilicity of a reagent.

溶剂可以显著影响试剂的亲核性。

9.A good leaving group enhances the nucleophilicity of the attacking species.

良好的离去基团增强了攻击物种的亲核性。

10.The nucleophilicity of thiolates is often compared to that of alkoxides in substitution reactions.

在取代反应中，硫醇盐的亲核性常与醇盐进行比较。

作文

Nucleophilicity is a fundamental concept in organic chemistry that describes the tendency of a nucleophile to donate an electron pair to an electrophile. In simpler terms, it refers to how readily a species can act as a nucleophile, which is crucial in many chemical reactions. Understanding nucleophilicity (亲核性) is essential for predicting reaction mechanisms and outcomes in synthetic chemistry. To grasp the importance of nucleophilicity (亲核性), one must first understand what nucleophiles are. Nucleophiles are species that have a pair of electrons available for donation. They can be negatively charged ions or neutral molecules with lone pairs. Common examples include hydroxide ions (OH-), alkoxide ions (RO-), and ammonia (NH3). The ability of these species to donate their electron pairs determines their reactivity in various chemical processes. The strength of a nucleophile is influenced by several factors, including charge, electronegativity, steric hindrance, and solvent effects. For instance, negatively charged nucleophiles are generally more reactive than their neutral counterparts because they possess an extra electron, which enhances their ability to donate electrons. Furthermore, nucleophiles with lower electronegativity tend to be more reactive, as they hold onto their electrons less tightly, making them more willing to share them with electrophiles. Steric hindrance also plays a significant role in determining nucleophilicity (亲核性). Bulky nucleophiles may struggle to approach electrophiles due to spatial constraints, thus reducing their reactivity. On the other hand, smaller nucleophiles can easily access electrophilic centers, enhancing their reactivity. Solvent effects are another critical aspect; polar protic solvents can stabilize nucleophiles through hydrogen bonding, while polar aprotic solvents can enhance nucleophilicity by not forming such stabilizing interactions. In addition to these factors, the solvent used in a reaction can significantly impact nucleophilicity (亲核性). For example, in polar protic solvents, nucleophiles may be surrounded by solvent molecules that can hinder their ability to react. Conversely, in polar aprotic solvents, nucleophiles are less solvated and can react more readily, demonstrating higher nucleophilicity (亲核性). Understanding the nuances of nucleophilicity (亲核性) is vital for chemists, especially when designing synthetic pathways. For example, when synthesizing a specific compound, a chemist must choose the right nucleophile to ensure the desired reaction occurs efficiently. By considering the factors that influence nucleophilicity (亲核性), chemists can predict the most favorable conditions for a reaction, leading to higher yields and fewer by-products. In conclusion, nucleophilicity (亲核性) is a critical concept in organic chemistry that influences the reactivity of nucleophiles in various chemical reactions. By understanding the factors that affect nucleophilicity, such as charge, electronegativity, steric hindrance, and solvent effects, chemists can make informed decisions when designing reactions. This knowledge not only enhances our understanding of chemical processes but also improves our ability to synthesize complex molecules effectively.

亲核性是有机化学中的一个基本概念，描述了亲核体向亲电体捐赠电子对的倾向。简单来说，它指的是物质作为亲核体的反应能力，这在许多化学反应中至关重要。理解nucleophilicity（亲核性）对于预测反应机制和合成化学中的结果是必要的。 要掌握nucleophilicity（亲核性）的重要性，首先必须了解什么是亲核体。亲核体是指具有可供捐赠的电子对的物质。它们可以是带负电荷的离子或具有孤对电子的中性分子。常见的例子包括氢氧根离子（OH-）、烷氧根离子（RO-）和氨（NH3）。这些物质捐赠电子对的能力决定了它们在各种化学过程中的反应性。 亲核体的强度受多个因素影响，包括电荷、电负性、空间位阻和溶剂效应。例如，带负电荷的亲核体通常比其中性对应物更具反应性，因为它们具有额外的电子，这增强了它们捐赠电子的能力。此外，电负性较低的亲核体往往更具反应性，因为它们对电子的束缚较弱，更愿意与亲电体分享电子。 空间位阻也在决定nucleophilicity（亲核性）方面发挥重要作用。体积较大的亲核体可能由于空间限制而难以靠近亲电体，从而降低其反应性。另一方面，较小的亲核体可以轻松接触亲电中心，从而增强其反应性。溶剂效应是另一个关键方面；极性质子溶剂可以通过氢键稳定亲核体，而极性非质子溶剂则可以通过不形成这种稳定相互作用来增强亲核性。 除了这些因素，反应中使用的溶剂也会显著影响nucleophilicity（亲核性）。例如，在极性质子溶剂中，亲核体可能被溶剂分子包围，这可能妨碍它们的反应能力。相反，在极性非质子溶剂中，亲核体的溶剂化程度较低，可以更容易地反应，表现出更高的nucleophilicity（亲核性）。 理解nucleophilicity（亲核性）的细微差别对于化学家尤为重要，尤其是在设计合成路径时。例如，在合成特定化合物时，化学家必须选择合适的亲核体，以确保所需的反应有效进行。通过考虑影响nucleophilicity（亲核性）的因素，化学家可以预测反应的最有利条件，从而提高产率并减少副产物。 总之，nucleophilicity（亲核性）是有机化学中的一个关键概念，影响着亲核体在各种化学反应中的反应性。通过理解影响亲核性的因素，如电荷、电负性、空间位阻和溶剂效应，化学家可以在设计反应时做出明智的决策。这一知识不仅增强了我们对化学过程的理解，也提高了我们有效合成复杂分子的能力。