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

官能基は、分子の特性に影響を与える原子の共有結合したセットです。
同じ官能基を含む分子は、多くの場合、同様の特性を示し、同様の反応をします。
官能基に名前を付けることで、分子内の原子を迅速に同定することができ、有機化学や生化学に役立っています。 
炭化水素は有機分子の基礎であり、さまざまな数の炭素原子と水素原子を含んでいます。これらには、アルカン、アルケン、およびアルキンが含まれます。アルカンの炭素原子は単結合で結合していますが、アルケンとアルキンはそれぞれ二重結合または三重結合を含んでいます。
炭化水素は閉じたリングを形成することができます。環が単結合のみを含む場合、それはシクロアルカンと呼ばれます。炭素が単結合と二重結合を交互に繰り返すことによって結合している場合、それは芳香環またはアリール基と呼ばれます。
最も単純な非炭素含有基の1つは、酸素原子と水素原子を含むヒドロキシル基です。メタノール、水、炭水化物など、いくつかの化合物の重要な成分です。
官能基の別のカテゴリーはカルボニル基で、炭素と酸素が二重結合で結合しています。カルボニル含有基には、アルデヒド基、ケトン基、エステル基、カルボキシル基などの官能基が含まれます。
アルデヒドは水素とカルボニルに結合した可変基またはR基を持ち、ケトンは2つの可変基を持っています。R基はしばしば炭化水素を表しますが、他の基や原子の場合もあります。 
アルデヒドとケトンは、炭水化物の重要な官能基です
エステルは、R基と酸素に挟まれたカルボニル基、一方、カルボン酸(カルボキシル基)は、R基とアルコールに挟まれたものです。脂質にはエステルが含まれ、アミノ酸にはカルボン酸が含まれています。
アミノ酸には、アミン基またはアミノ基と呼ばれる別の一般的な官能基もあります。アミンは、水素とR基の組み合わせに結合した孤立電子対を持つ窒素を持っています。アミノ酸はタンパク質の構成要素です。 
リン酸基は、4つの酸素に結合したリンであり、すべての生物の遺伝物質であるDNAに一般的に見られます。また、タンパク質に付着させてその機能を変えることもできます。

官能基

官能基とは特徴的な性質を持つ原子群のことであり、炭素骨格に結合すると、その性質を変化させます。例えば、ある官能基が分子上に存在すると親水性になり、他の官能基が存在すると疎水性になります。これらの官能基は、有機化学には欠かせないものであり、炭水化物、タンパク質、脂質、核酸などの生体分子の重要な構成要素です。それぞれの官能基は特徴的な原子配置を有し、その官能基を構成する原子の組み合わせに応じた名前が割り当てられています。
 炭化水素 
 炭素原子間の強く安定した結合は、鎖や枝、環などを含む複雑な分子を作り出す。このような化合物の化学を有機化学といいます。炭化水素は、炭素と水素だけで構成される有機化合物です。アルカンは飽和炭化水素であり、単結合しか持たません。アルケンは、1つ以上の炭素-炭素二重結合を含む。アルキンは、1つ以上の炭素-炭素三重結合を含む。芳香族炭化水素は環構造を持ちます。これらはアリール基という官能基しても知られています。
 アルコール類とエーテル類 
 炭化水素ではない多くの有機化合物は、炭化水素の誘導体と考えることができます。炭化水素の誘導体は、炭化水素の1つ以上の水素原子を官能基で置き換えることで作られます。炭化水素誘導体の特性は、官能基によって大きく左右されます。水酸基として知られる –OH基は、アルコールの官能基です。R–O–R–基は、エーテルの官能基です。
 アルデヒド類、ケトン類、カルボン酸類、エステル類 
 カルボニル基に関連する官能基には、アルデヒドの –CHO基、ケトンの –CO–基、カルボン酸の –COOH基、エステルの –COOR基などがあります。これらの有機分子では、炭素と酸素の二重結合であるカルボニル基が重要な構造となっています。アルデヒドはカルボニル炭素原子に少なくとも1つの水素原子が結合しており、ケトンはカルボニル炭素原子に2つの炭素基が結合しており、カルボン酸はカルボニル炭素原子に水酸基が結合しており、エステルはカルボニル炭素原子に結合した他の炭素基に酸素原子が結合しています。これらの化合物はいずれも、アルコール基の炭素原子に対して、酸化された炭素原子を含んでいます。
 アミン類 
 有機物の骨格に窒素が加わると、2種類の分子が生まれます。炭化水素の骨格に窒素原子が結合した化合物は、アミンに分類されます。
 上記の文章は以下から引用しました。 <a href="https://openstax.org/books/chemistry-2e/pages/20-1-hydrocarbons">Openstax, Chemistry 2e, Section 20.1: Hydrocarbons</a>, <a href="https://openstax.org/books/chemistry-2e/pages/20-2-alcohols-and-ethers">Openstax, Chemistry 2e, Section 20.2: Alcohols and Ethers, </a><a href="https://openstax.org/books/chemistry-2e/pages/20-2-alcohols-and-ethers">Openstax, Chemistry 2e, Section 20.3: Aldehydes, Ketones, Carboxylic Acids, and Esters,</a> and <a href="https://openstax.org/books/chemistry-2e/pages/20-4-amines-and-amides">Openstax, Chemistry 2e, Section 20.4: Amines and Amides.</a>

官能基は、特徴的な特性を持つ原子のグループであり、分子の炭素骨格に結合すると、分子の特性を変化させます...

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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

chemistry

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Functional Groups in Organic Chemistry

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