Based on the IUPAC system, tertiary butyl group is named as
- 2-methylpropyl
- 2, 2-dimethylethyl
- 2-methylbutyl
- 1, 3-dimethylbutyl
Solution

Butyl is a four carbon alkyl radical or substituent group with general chemical formula $\mathrm{C}_4 \mathrm{H}_9$ - If methyl group connects to central carbon then, it is tertiary butyl group.
Asked in: AP EAMCET 2021 (24 Aug Shift 1)
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