nucleophile

简明释义

英[ˈnjuːklɪəʊˌfaɪl]美[ˈnʊkliəˌfaɪl;ˈnjʊkliəˌfaɪl]

n. 亲核试剂

英英释义

单词用法

同义词

反义词

例句

1.A new olefination methodology based on the nucleophile attacking fluorinated phosphonates.

亲核试剂对全氟酰基膦酸酯进攻为基础的新合成方法学。

2.A new olefination methodology based on the nucleophile attacking fluorinated phosphonates.

亲核试剂对全氟酰基膦酸酯进攻为基础的新合成方法学。

3.Amines can engage in nucleophile substitution reaction with alky.

胺能参加与卤代烷的亲核取代反应。

4.In organic chemistry, a nucleophile is an electron-rich species that can donate an electron pair to form a chemical bond.

在有机化学中，亲核试剂是一个富含电子的物质，可以捐赠一对电子以形成化学键。

5.The reaction between a nucleophile and an electrophile is fundamental in many organic reactions.

一个亲核试剂和一个电亲体之间的反应在许多有机反应中是基础。

6.Hydroxide ions (OH-) act as a strong nucleophile in substitution reactions.

氢氧根离子（OH-）在取代反应中作为强亲核试剂。

7.In the presence of a good leaving group, a nucleophile can effectively initiate a nucleophilic substitution.

在良好的离去基团存在下，亲核试剂可以有效地启动亲核取代反应。

8.A common example of a nucleophile is ammonia (NH3), which can attack carbonyl compounds.

一个常见的亲核试剂是氨（NH3），它可以攻击羰基化合物。

作文

In the realm of organic chemistry, the term nucleophile refers to a species that donates an electron pair to form a chemical bond in a reaction. This characteristic makes nucleophiles essential players in various chemical reactions, particularly in nucleophilic substitution and addition reactions. Understanding the role of nucleophiles can greatly enhance one's grasp of reaction mechanisms and the behavior of different molecules in organic synthesis. To better understand what a nucleophile is, consider its name: 'nucleo-' comes from the nucleus, which is the positively charged center of an atom, while '-phile' means 'loving' or 'attracted to'. Therefore, a nucleophile is literally an entity that is attracted to positive charges or electron-deficient centers in other molecules. Common examples of nucleophiles include negatively charged ions such as hydroxide (OH⁻) and halides (like Cl⁻), as well as neutral molecules with lone pairs of electrons, such as ammonia (NH₃) and water (H₂O). When a nucleophile approaches a positively charged center, it can donate its electron pair to form a new bond. This process is fundamental in many biochemical pathways, including enzyme-catalyzed reactions where nucleophiles interact with electrophiles—species that are electron-deficient. For instance, in the reaction between an alcohol and an alkyl halide, the alcohol acts as a nucleophile, attacking the carbon atom bonded to the halogen, leading to the formation of an ether or an alkyl group. The strength of a nucleophile can vary significantly, influenced by factors such as charge, electronegativity, and solvent effects. Generally, negatively charged species are stronger nucleophiles than their neutral counterparts because they possess extra electrons that can be shared. Furthermore, nucleophiles can be classified into strong and weak categories based on their reactivity. Strong nucleophiles, like alkoxides and thiolates, react readily with electrophiles, while weaker ones, such as water, may require more favorable conditions to participate in reactions. In conclusion, the concept of nucleophiles is crucial in understanding organic chemistry and reaction mechanisms. By recognizing how these electron-rich species interact with electron-poor centers, chemists can predict the outcomes of reactions and design new synthetic pathways. As we delve deeper into the world of organic reactions, the significance of nucleophiles becomes increasingly apparent, making them indispensable tools in the chemist's toolkit. Ultimately, mastering the concept of nucleophiles will not only enhance one's knowledge of chemistry but also open doors to innovative applications in pharmaceuticals, materials science, and beyond.

在有机化学的领域中，术语亲核试剂指的是一种在反应中捐赠电子对以形成化学键的物质。这一特性使得亲核试剂在各种化学反应中成为重要的参与者，特别是在亲核取代和加成反应中。理解亲核试剂的角色可以极大地增强人们对反应机制及不同分子在有机合成中行为的理解。 要更好地理解什么是亲核试剂，可以考虑它的名称：“nucleo-”来自于原子内部的核，而“-phile”意味着“爱”或“吸引”。因此，亲核试剂字面上就是一种被正电荷或其他分子中的电子缺乏中心吸引的实体。常见的亲核试剂包括负电荷离子，例如氢氧根（OH⁻）和卤素（如Cl⁻），以及带有孤对电子的中性分子，如氨（NH₃）和水（H₂O）。 当亲核试剂接近正电荷中心时，它可以捐赠其电子对以形成新的键。这一过程在许多生化路径中都是基础，包括酶催化反应，其中亲核试剂与电亲体——电子缺乏的物质相互作用。例如，在醇和卤烷之间的反应中，醇作为亲核试剂，攻击与卤素相连的碳原子，从而形成醚或烷基。 亲核试剂的强度可能会显著变化，受电荷、电负性和溶剂效应等因素的影响。通常情况下，带负电荷的物质比中性物质更强，因为它们拥有额外的电子可以共享。此外，亲核试剂可以根据其反应性分为强和弱两类。强亲核试剂，如醇盐和硫醇盐，能迅速与电亲体反应，而较弱的如水则可能需要更有利的条件才能参与反应。 总之，亲核试剂的概念在理解有机化学和反应机制方面至关重要。通过认识这些富含电子的物质如何与电子匮乏中心相互作用，化学家可以预测反应的结果并设计新的合成路径。当我们深入探索有机反应的世界时，亲核试剂的重要性变得愈加明显，使其成为化学家工具箱中不可或缺的工具。最终，掌握亲核试剂的概念不仅将增强一个人对化学的理解，还将为药物、材料科学等领域的创新应用打开大门。