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Basic Information:

It is the very basic information you must know before starting IUPAC Nomenclature.

Alkane:

1. Locate the longest continuous chain of carbon atoms; this chain determines the parent name for the alkane.
2. Number the longest chain beginning from the end of the chain nearer the substituent.
3. Locate the substituent/s on the longest carbon chain and write with respective numbers.
4. When two or more substituents are present, give each substituent a number corresponding to its location on the longest chain, alphabetically.
5. When two substituents are present on the same carbon atom, use that number twice.
6. When two or more substituents are identical, indicate by the use of the prefixes; di, tri, tetra and so on. Then make certain that each substituent has a number. Commas are used to separate numbers from each other. A hyphen is used to separate numbers from words.
7. When two chains of equal lengths compete for the selection as the parent chain, chose the chain with the greater number of substituents.
8. When branching first occurs at an equal distance from either end of the longest chain, choose the name that gives the lower number at the first point of difference.

Alkene:

9. Locate the longest continuous chain that contains the C = C as the parent chain. Change the ending of the name of the alkane of identical length from ‘ane’ to ‘ene’.
10. Number the chain to include both carbon atoms of the double bond. Numbering begins from the end nearer to the double bond.
11. Designate the location of the double bond by using the number of the first atom of the double bond as a prefix.
12. If the parent chain contains more than one double bond, they are alkadiene for two, alkatrienes for three and so on.

Alkynes:

13. Locate the longest continuous carbon chain containing a triple bond. Change the ending of the name of the alkane of identical length from ‘ane’ to ‘yne’
14. The position of the triple bond is assigned by the minimum number in the chain.
15. If a hydrocarbon contains more than one triple bond, it is named as alkadiyne for two, alkatriyne for three and so on.
16. If both double and triple bonds are present in the compound then the ending enyne is given as;
    • The lowest possible number is assigned to the double or triple bond irrespective of whether ene or yne gets the lower number.
    • In case a double and a triple bond are present at identical positions, the double bond is given the lower number.

Alkyl halide (R-X):

17. Number the carbon atoms in the chain so that the carbon atom bearing the functional group (F, Cl, Br, I) gets the lowest possible number.

Alcohols (R-OH):

18. The longest chain of carbon atoms containing the hydroxyl group is taken as the parent hydrocarbon. The ending ‘e’ of an alkane is replaced by ‘ol’.
19. The position of the OH group is indicated by a number placed before the name. The carbon chain is numbered, starting from the end where carbon attached to the OH group gets the lowest possible number.
20. If more than one OH group are attached, they are indicated by an appropriate suffix diol, triol, etc.
21. The unsaturated alcohols are named in such a way that the hydroxyl group rather than the point of unsaturation gets the lower number`.

Aldehyde (-CHO):

22. Start the numbering of the longest continuous carbon chain from carbonyl carbon.
23. The ending ‘e’ from the derived alkane is replaced by “al” to name the aldehydes.

Ketones (R-CO-R):

24. Number the longest continuous carbon chain from that end which is nearest to the carbonyl group.
25. The positions of the carbonyl group and other groups are indicated by numbers.
26. The ending ‘e’ from the derived alkane is replaced by “one”.

Carboxylic Acid (-COOH):

27. Start the numbering of the longest continuous carbon chain from carbonyl carbon.
28. The ending ‘e’ from the derived alkane is replaced by “oic Acid”.

Ether (R-O-R):

29. The Large alkyl (R) group is taken as the parent molecule and given the last name (suffix) while the smaller alkyl group along with oxygen is used as a prefix and given the name alkoxy. (methoxy, ethoxy, propoxy, etc.)

Benzene (Monocyclic aromatic hydrocarbons and their derivatives)

30. Mono-substituted benzene derivatives are named by writing substituent first and benzene in the last but both as a single word.
31. In naming the di-substituted benzene, when both substituents are the same give rise to three isomeric products designated as ortho (1,2) or (1,6), meta (1,3) or (1,5) and para (1,4).
    If two or more substituents are different, then the substituent that is treated as a high-priority group is given the number 1 position in the benzene ring. Other groups are numbered by counting from position 1 in the manner which gives them the lowest number.
    Priority order:
    -COOH, -CN, -CHO, -COCH₃, -OH, -NH₂, -OR, -R
32. If two substituents are different and they are not present in the priority order list, they are named in alphabetical order. The last-named substituent will be at position 1.
33. If there is a substituent on the ring which gives a special name to the molecule, then a special name is used as the parent name of the molecule.

Multi-functional Groups:

34. If two functional groups are present simultaneously in a compound then consider a priority. E.g. If –COOH and –OH groups are present in a compound, then “oic Acid” is placed in the last as the parent name and carboxylic acid is at first priority. While (-OH) is considered a substituent and named as hydroxy.

IUPAC Nomenclature Examples from Exercise (Chapter 8 class 12)

This video beautifully explains the IUPAC Nomenclature of organic compounds. video solves different kinds of important examples to illustrate that how to name organic compounds with the International Union of pure and applied chemistry. These examples are present in the exercise of the book at the end.

Common Names and Trivial Names (Chapter 8 Class 12)

This video shows how to name organic compounds in a traditional way. These names are also called common names or trivial names. For example, barbituric acid was named after Barbara and acetic acid was named acetum means vinegar. Methane gas is named due to its presence in marshy places. It is also called Marsh gas

Correction of incorrect IUPAC names (Chapter 8 Class 12)

This is a unique video to correct the names, given in the textbook exercise of class 12. These names are incorrectly written and are similar to the IUPAC system. Now the task is to correct these incorrect IUPAC names.

Convert IUPAC Name to Structural formula (Chapter 8 Class 12)

This video describes the nomenclature of alkene and alkyne. It tells that how we name alkene and alkyne by the help of different examples from the exercise of the book 12. There are important examples through which you can write structural formula, if you are given IUPAC name.

Zoom demo Class

It is an extra lecture delivered for the sake of a demonstration on ZOOM, covering the nomenclature of carboxylic acid especially common names.