Question

The IUPAC name of

• A. 6-Ethyl-3, 3-dimethylcyclohex-1-ene
• B. 3-Ethyl-6, 6-dimethylcyclohex-1-ene
• C. both a and b are accepted
• D. Neither a nor b

Answer 1

The correct option is A

6-Ethyl-3, 3-dimethylcyclohex-1-ene

In this compound, the parent chain is the one containing cyclic carbon.

Now, we number in the following way.

Because more substituted will get the lower number.

$\to$ethyl group at $C_5$

$\to$Two methyl group at $C_3$

Therefore, it will be

6-Ethyl-3-3-Dimethylcyclohex-1-ene

not

3,3-Dimethyl-6-ethylcyclohex-1-ene

Because we use alphabetical order and Di- is not considered for the alphabetical order.