Name: functional groups in organic chemistry
Uploaded: 2020-09-24T15:06:53.000Z
Duration: 2 min 45 s
Channel: JoVE

官能团是影响分子性质的 共价键原子组。含有相同官能团的分子往往表现出相似的性质，并发生类似的反应。命名官能团可以快速识别 分子中的原子，这在有机化学 和生物化学中很有用。碳氢化合物是有机分子的基础，含有不同数量的碳原子和氢原子。这些化合物包括烷烃、烯烃和炔烃。烷烃中的碳原子通过单键连接，而烯烃和炔烃分别带有 双键或三键。碳氢化合物可形成闭环。如果这个环只包含单键，则称为环烷烃。如果碳原子通过交替的 单键和双键连接在一起，则称为芳环或芳基。最简单的不含碳基团之一是羟基，它含有一个氧原子 和一个氢原子。它是几种化合物的重要成分，例如甲醇、水和碳水化合物。另一类官能团是羰基，它含有一个碳和一个氧，通过双键连接在一起。含羰基的基团包括官能团，例如醛、酮、酯和羧基。醛带有氢和一个连接在羰基上可变基团 或 R 基团，而酮带有 两个可变基团。R 基团通常代表烃类，但也可以是其他基团或原子。醛和酮是碳水化合物中的 重要官能团 酯由一个羰基和它两侧的 一个 R 基团和一个氧组成，而羧酸，或羧基，则在两侧 带有一个 R 基团和一个醇。脂类含有酯，而氨基酸含有羧酸。氨基酸还具有另一个常见的官能团，称为胺或氨基。胺有一个带孤电子对的氮原子，与氢和 R 基团的组合连接。氨基酸是蛋白质的基本组成部分。磷酸基团是磷与四个氧的结合，通常存在于所有活生物体的 遗传物质 DNA 中。它也可以附着在蛋白质上，改变它们的功能。

官能团

官能团是一组具有特征性质的原子，当它与分子的碳骨架相连接时，它会改变该分子的性质。 例如，分子上存在某些官能团会使其具有亲水性，而其他分子则会使其具有疏水性。 这些官能团是有机化学和生物分子的重要组成部分，如碳水化合物，蛋白质，脂质和核酸的不可或缺的一部分。 每个官能团都是原子的唯一排列，并为组成该组的原子组合分配一个名称。 
 碳氢化合物 
 碳原子之间的强而稳定的键会产生含有链，分支和环的化合物分子。 这些化合物的化学特性称为有机化学。 碳氢化合物是仅由碳和氢组成的有机化合物。 烷烃是饱和碳氢化合物—即仅含单键的碳氢化合物。 碱含有一个或多个碳双键。 碱含有一个或多个碳 - 碳三联键。 芳香烃含有环状结构。 他们也被称为亚基组。 
 酒精和醚 
 许多非碳氢化合物的有机化合物可以被视为碳氢化合物的衍生物。 碳氢化合物衍生物可以通过用官能团替代一个或多个碳氢化合物氢原子来形成， 含有碳或氢以外元素的至少一个原子。 碳氢化合物衍生物的性质主要由官能团决定。 OH 组称为羟基组，是酒精的官能团。 R – O – R –组是乙醚的官能团。 
 醛，酮，羧基酸和酯 
 与碳基组相关的官能团包括醛的– CHO 组，酮的– CO 组，羧酸的– COOH 组和酯的– COOR 组。 碳基组是碳氧双键，是这些类有机分子的关键结构： 醛含有至少一个与碳基碳原子相连的氢原子，酮含有两组碳基碳原子，羧基酸含有一组与碳基碳原子相连的羟基， 酯中含有一个连接到另一个碳组的氧原子，该碳原子组与碳基碳原子相连。 所有这些化合物都含有与酒精类碳原子相关的氧化碳原子。 
 胺类 
 将氮添加到有机框架中会导致两个分子系列。 碳氢化合物框架中含有氮原子键合的化合物被归类为胺类。 
 本文改编自<a href="https://openstax.org/books/chemistry-2e/pages/20-1-hydrocarbons"> Openstax, Chemistry 2e, Section 20.1 ：烃类</a>，<a href="https://openstax.org/books/chemistry-2e/pages/20-2-alcohols-and-ethers"> Openstax, Chemistry 2e, 第 20.2 节：醇类和醚，</a><a href="https://openstax.org/books/chemistry-2e/pages/20-2-alcohols-and-ethers"> Openstax ， Chemistry 2e ，第 20.3 节：醛，酮， 羧基酸和酯</a>以及<a href="https://openstax.org/books/chemistry-2e/pages/20-4-amines-and-amides"> Openstax ， 化学 2e 第 20.4 节：胺和酰胺。 </a>

官能团是一类具有特征性质的原子团，当其连接到分子的碳骨架上时，会改变该分子的性质……

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Functional Groups

functional groups in organic chemistry

Functional groups in organic chemistry are groups of atoms that give molecules specific properties. When these groups attach to a carbon skeleton, they can change how the molecule behaves. Some functional groups make a molecule hydrophilic, or water-attracting. Others make it hydrophobic, or water-repelling.

Functional groups are a key part of organic chemistry and are also found in major biological molecules. They appear in carbohydrates, proteins, lipids, and nucleic acids. Each functional group has a unique arrangement of atoms and a name based on that arrangement.

Hydrocarbons are organic compounds made of only carbon and hydrogen. Strong carbon-carbon bonds can build long chains, branches, and rings. Saturated hydrocarbons are called alkanes because they contain only single bonds. Alkenes contain one or more carbon-carbon double bonds, while alkynes contain one or more carbon-carbon triple bonds. Aromatic hydrocarbons contain ring structures and are also known as aryl groups.

Many organic compounds are not hydrocarbons, but they can be formed from hydrocarbons. In a hydrocarbon derivative, one or more hydrogen atoms are replaced by a functional group that contains at least one atom other than carbon or hydrogen. The functional group usually determines the properties of the derivative. The hydroxyl group, written as –OH, is the functional group of an alcohol. The –R–O–R– group is the functional group of an ether.

Other important functional groups are related to the carbonyl group. The carbonyl group is a carbon-oxygen double bond. Aldehydes contain the –CHO group, ketones contain the –CO– group, carboxylic acids contain the –COOH group, and esters contain the –COOR group. In aldehydes, at least one hydrogen is attached to the carbonyl carbon. In ketones, two carbon groups are attached to that carbon. Carboxylic acids have a hydroxyl group attached to the carbonyl carbon, and esters have an oxygen atom linked to another carbon group at that position.

These carbonyl-based compounds contain oxidized carbon atoms compared with the carbon atom in an alcohol group. Adding nitrogen to an organic framework forms another important family of molecules. Compounds with a nitrogen atom bonded within a hydrocarbon framework are called amines.

Functional Groups in Organic Chemistry

functional groups

Functional groups in organic chemistry are groups of atoms that give molecules specific properties. When these groups attach to a carbon skeleton, they can change how the molecule behaves. Some functional groups make a molecule hydrophilic, or water-attracting. Others make it hydrophobic, or water-repelling. Functional groups are a key part of organic chemistry and are also found in major biological molecules. They appear in carbohydrates, proteins, lipids, and nucleic acids. Each functional...

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key terms and concepts

Learn how functional groups change the properties of organic molecules, from hydrocarbons and alcohols to carbonyl compounds and amines.

Functional Groups in Organic Chemistry | JoVE K12

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Functional Groups in Organic Chemistry

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