- The International Union of Pure and Applied Chemistry (IUPAC) is an international non-governmental organization that helps to tackle the problems or issues concerning chemical science around the world.
- IUPAC nomenclature of organic compounds can be treated as the systematic and proper approach for the nomenclature of organic compounds as per norms and rules recommended by the International Union of Pure and Applied Chemistry (commonly abbreviated to IUPAC).
Rules Of Nomenclature
As per the Guidelines set by IUPAC, the nomenclature of compounds must follow the following steps:
- The Longest Chain Rule: The parent chain of the given compound generally the longest chain of carbon atoms is chosen, and itis preferred to be in the form of a straight-chain or a chain of any other shape.
- The Lowest Set of Locants: The carbon atoms belonging to the parent chain must be numbered using natural numbers and beginning from the end in with the least number of the carbon atom which carries the substituents.
- Multiple instances of the same substituent: The prefixes that indicate the total number of the same substituent group in the given compound is mentioned, such as di, tri, etc.
- Naming of different substituents: In the organic compounds that contain multiple substituents, the corresponding substituents are arranged in alphabetical order of names as per the IUPAC nomenclature of compounds given.
- The naming of different substituents present at the same positions: When two different substituent groups are present at the same position of the compound, the substituents are named in ascending alphabetical order.
The format for the IUPAC nomenclature of the Compound can be given as: Locant + Prefix + Root + Locant + Suffix
We are given with the compound CH3CH2CH2COOH
We need to name the given compound as per the IUPAC nomenclature
Nomenclature of given compund
- The compound has -COOH functional group. Hence we can start numbering the parent chain from the carbon-containing functional group. So the group -COOH will have the numbering as 1 and the very next carbon on left with CH2 group as 2, then next carbon with CH2 group as 3 and the last carbon with CH3 group as 4.
- As per the IUPAC norm the chain with four carbon atoms is termed as Bute
- Since it is alkane (Only single bond) the name comprises the name ane
- Functional group is acid
- Hence combining all the above points the IUPAC name for a given compound is Butanoic acid.
Butanoic acid in common language is termed as Butyric acid.