as the longest chain of carbon is of seven carbons it is wrong namecrrt name is 4-ethyl 3-methyl heptane

Explanation of the incorrect IUPAC name "2,3-Diethylhexane"

The given name "2,3-Diethylhexane" does not follow the correct rules of the International Union of Pure and Applied Chemistry (IUPAC) nomenclature for organic compounds. Let's break down the reasons why this name is incorrect:

Lack of proper numbering
In IUPAC nomenclature, the carbon chain in an organic compound should be numbered in a way that gives the substituents the lowest possible locants. The locant numbers are assigned based on the position of the substituents on the main chain.

In the name "2,3-Diethylhexane," the numbering suggests that there are two ethyl groups (CH3-CH2-) located at positions 2 and 3 of the hexane chain. However, this is incorrect because the ethyl groups are actually attached to carbon atoms 3 and 4, not 2 and 3. Therefore, the numbering is incorrect, leading to an incorrect name.

Correct nomenclature
To name the compound correctly, we need to follow the IUPAC rules. Here is the correct systematic name for the given compound, step-by-step:

1. Identify the longest continuous carbon chain in the molecule. In this case, it is a six-carbon chain, so we use the prefix "hexane."

2. Number the carbon atoms in the chain starting from the end that gives the substituents the lowest possible locants. In this case, we start numbering from the end closest to the ethyl groups.

3. Name and locate the substituents. The compound contains two ethyl groups attached to carbon atoms 3 and 4. Therefore, we use the prefixes "3-ethyl" and "4-ethyl."

4. Combine the prefixes with the name of the parent chain. The systematic name for the given compound is "3,4-Diethylhexane."

Conclusion
The incorrect IUPAC name "2,3-Diethylhexane" violates the rules of proper numbering in organic compound nomenclature. The correct systematic name for the compound is "3,4-Diethylhexane," following the proper naming conventions outlined by the IUPAC.