Which are the IUPAC names of the following compound?

1. 5-(2', 2'-Dimethylpropyl)-decane

2. 4-Butyl-2,2-dimethylnonane

3. 2,2-Dimethyl -4- pentyloctane

4. 5-neo-Pentyldecane


(1, 4)
5-(2',2'-Dimethylpropyl)-decane 5-neo-pentyldecane
The IUPAC name for neopentyl groups is 2, 2 dimethyl propyl.