Question

IUPAC name of the compound

$H_{2}N-\stackrel{O}{\stackrel{||}{C}}-\underset{C{H}_3}{\underset{|}{\underset{CH-C{H}_3}{\underset{|}{CH}}}}-C(C{H}_3{)}_3$?

• A. 3-Methyl-2-(1, 1-dimethylethyl)butanamide
• B. 3, 3-Dimethyl-2-(1-methylethyl)butanamide
• C. 2, 2-Dimethyl-2-(1-methylethyl)butanamide
• D. None of the above

Answer 1

The correct option is B

3, 3-Dimethyl-2-(1-methylethyl)butanamide

Let's decide about the parent chain first. There are two possibilities.

In the figure I $\Rightarrow$ Number of substituents = 2

{at $C_2$ and $C_3$}

In the figure II $\Rightarrow$ Number of substituents = 3

{at $C_2,C_3$ and again $C_3$}

Therefore, the parent chain will be

word root = But

Only single bonds between carbon.

Therefore, primary suffix = ane

Functional group $\to N{H}_3\Rightarrow$ Amide

The secondary suffix - amide

So, it will be butanamide

Now, let's take a look at substituents.

There are two methyl groups at $C_3$.

Therefore, 3,3 -dimethyl

And for $C_2$ the primary chain consists of two carbons and one methyl group attached to first carbon.

Therefore, 2-(1-methylethyl)

So, the IUPAC name of the compound is 3,3-Dimethyl -2-(1-methylethyl)butanamide