The IUPAC name of the following compound is :

$(a)\;3,4,4 -Trimethylheptane \\(b)\;3,4,4 - Trimethyloctane \\(c)\;2- Butyl -2-methyl-3 -ethylbutane \\(d)\;2-Ethyl-3,3-dimenthylheptane$

Longest carbon chain
$3,4,4 - Trimethyloctane$ is correct.
Hence b is the correct answer.
answered Mar 5, 2014 by