Answer
The more common name for the ( 1,1 -dimethylethyl ) group is: Isobutyl group.
Work Step by Step
1. Write the biggest carbon chain, and number its carbons:
- It is: "ethyl", so we must draw this chain: $^1CH_3 − \space^2 CH_2−$
2. Now, add the other groups:
- Since its represented by: "1, 1-dimethyl", we should attach two methyl groups ($CH_3−$) to the first carbon of the chain, which will lose two hydrogen to do such thing.
- The final chemical formula is: $(CH_3)_2-CHCH_2-$
3. Finally, name it properly:
- As we can see at the top of page 92, ( 1,1 -dimethylethyl ) is a "Isobutyl Group"