Nomenclature Of Molecules Containing Substituents

Nomenclature of Functional groups 

Most organic molecules are built around functional groups. The name of the organic compound is determined by the name of the functional group and their bonding. That is why the titles of the functional groups must be explicit. The structure and qualities of functional groups are used to name them. The number of carbon atoms and their position serve as the primary basis for designating functional groups. There are some special requirements for nomenclature of functional groups, just as there are for other chemical compounds. Furthermore, the nomenclature of functional groups must be ordered in accordance with the functional group priority order. There are some general functional groups, and nearly all organic molecules fall into one of those functional group categories.

What exactly is an Organic Compound?

Organic substances are chemical compounds made up of carbon atoms. One or more covalent bonds between carbon and other atoms produce these molecules. Organic molecules also contain carbon and hydrogen bonds. Carbon atoms are the primary constituents of organic compounds due to their catenation characteristics. In chemistry, there are a plethora of organic compounds. Organic compounds are formed by almost all carbon compounds. However, some carbon molecules, such as cyanide salts, carbonate anion salts, and carbon dioxide, cannot form organic compounds. Organic compounds include allotropes, which are difficult pure forms of carbon. Many chemical molecules have a variety of functional groups.

What exactly is a Functional Group?

A functional group is a solitary atom or a compound that is formed in a unique way. It is also the region of an organic molecule that is the most reactive. Compounds with the same functional group undergo the same sort of reaction. As both C2H5OH (ethanol) and C3H7OH (propanol) have the same functional group, OH, they trigger the same type of reactions. When the chemical is treated with sodium metal, it releases hydrogen. When naming an organic compound containing a functional group, we must adhere to the priority order in IUPAC nomenclature.

Functional Group Priority Order in IUPAC Nomenclature

When a molecule has numerous functional groups connected to it, the precedence order of functional groups in IUPAC nomenclature must be followed when identifying functional groups. Starting with the functional groups with the highest priority, according to the table:

1.Carboxylic Acid  (prefix: carboxy-, suffix: -carboxylic acid or -oic acid) example -:Ethanoic acid 

2.Sulfonic acid (prefix: sulfo-, suffix: -sulfonic acid)Example-: Benzenesulfonic acid 

3.Ester (prefix: alkoxycarbonyl-, suffix: -oate)  for example: methyl ethanoate

4.Acid Halide -:(prefix: halo carbonyl-, suffix: -oyl halide) example-:Ethanoyl chloride.

5.Amide (prefix: carbamoyl-, suffix: -carboxamide or -amide) example-: ethanamide

6..Nitrile (prefix: cyano-, suffix: -nitrile)Example -: Ethanenitrile 

7. Aldehyde (prefix: formyl-, suffix: -al or carbaldehyde)Example-: Ethanal 

8.Ketone (prefix: oxo-, suffix: -one) example-:2-propanone 

9.Alcohol, (prefix: hydroxy-, suffix: -ol) example- Methanol 

Nomenclature  of Functional Groups 

There are certain precise stages for organic compound nomenclature. These stages should also be followed by the naming conventions of functional groups. The general steps are as follows:

1.First, the length of the longest carbon chain must be established.

2.All parent chain substituents must be specified.

3.The compound’s functional group will be determined next.

4 The number of carbon compounds and carbon-hydrogen bonds must be determined.

5 The functional group will be designated in the final step, taking into account the aforementioned considerations and according to the IUPAC nomenclature regulations.

Nomenclature of Aldehyde 

The IUPAC nomenclature system gives aldehydes the distinctive suffix -al. H2C=O, for example, is methanal, also known as formaldehyde. Because an aldehyde carbonyl group must always be found at the end of a carbon chain, it is always assigned the #1 position in numbering and is not required to be included in the name. Several simple carbonyl-containing compounds have common names that are still used by IUPAC.

There is also a standard procedure for naming aldehydes and ketones. Common parent chain names, similar to those used for carboxylic acids, are used for aldehydes, and the suffix –aldehyde is appended at the end. Carbon atoms near the carbonyl group are frequently denoted by Greek letters in aldehyde common names. The atom closest to the carbonyl function is alpha, followed by beta, and so on.

If an aldehyde moiety OrganicCore AldehydesKetones3.png (-CHO) is joined to a ring, the suffix –carbaldehyde is appended to the ring’s name. In naming the ring, the carbon linked to this moiety will receive the #1 location number

Nomenclature of Ketones 

Ketones have a distinguishing suffix of -one in the IUPAC nomenclature system. A ketone carbonyl function can be found anywhere in a chain or ring, and its location is usually indicated by a number. Normally, chain numbering begins at the end closest to the carbonyl group. There is only one feasible location for a ketone carbonyl function, very simple ketones such as propanone and phenylethanone do not require a locator number. Ketones are given common names by first identifying both alkyl groups linked to the carbonyl and then adding the suffix -ketone. 

Conclusion

We conclude that In organic chemistry, there are nine common functional groups. All common groups are named in accordance with IUPAC nomenclature guidelines and the priority order of functional groups in IUPAC nomenclature. Organic chemistry’s most prevalent functional groups include aldehyde, amine, hydroxyl, ketone, phenyl, amino, ether, amide, and ester.