Question

Propose structures and give IUPAC names for the following:

1. A diethyldimethylhexane
2. A (3-methyl butyl)-substituted alkane

Short answer

a.

b.

Step-by-step solution

IUPAC (International Union Of Pure and Applied Chemistry)

IUPAC system is a method of naming various chemical compounds systematically. It is constituted by 4 parts,

IUPAC name= $\text{Locant\hspace{0.17em}+Prefix+Parent+Suffix}$

Locant tells us the position of the substituent, prefix tell us what the substituent is, parent suggest the length of the carbon chain (2,3,4 and so on) and the primary functional group is identified by the suffix part.

Step 2:

While writing the structure from the IUPAC names, we first write the parent chain first, then according the numbering indicated in the name, we place principal functional groups and other substituents on carbon atoms and then add hydrogen to satisfy the valency of each carbon atom.

a. A diethyldimethylhexane

Here, first make a parent carbon chain of 6 carbon atoms as the given IUPAC name suggests. Now place two ethyl groups on a any single carbon (as the position of substituent is not given) and two methyl groups on any other one,such that the longest chain rule is not violated. The structure you get is-

A diethyldimethylhexane

b.

A (3-methyl butyl)-substituted alkane

For this, first take any parent carbon chain say, pentane (5 carbon chain). Now replace hydrogen atom of any of the carbon parent carbon chain with 3-methyl butyl group and this becomes a (3-methyl butyl)-pentane.

(3-methyl butyl)-substituted alkane