Question

Write the IUPAC name of ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{CH}={\mathrm{CH}}_2$.

Answer 1

IUPAC name:

• IUPAC (International Union for Pure and Applied Chemistry) name is a worldwide used chemical name.
• There are certain rules for naming different chemical compounds.

Naming the given compound:

The general formula for naming the compound is $\mathrm{Locant}+\mathrm{Prefix}+\mathrm{Root}+\mathrm{Locant}+\mathrm{Suffix}$

Step 1: Finding the number of carbon atoms and highest carbon chan:

• Here, there are five carbon atom which gives a root word of pent-

$\mathrm{C}-\mathrm{C}-\mathrm{C}-\mathrm{C}-\mathrm{C}$

Step 2: Finding and positioning substituents:

• There is no substituent present in this compound.

Step 3: Identifying functional groups, primary and secondary suffixes and their positioning:

• No functional groups are present in this compound.
• Here, the primary suffix is -ene as there is a double bond, with no secondary suffix and prefix present.
• The positioning of the suffix -ene should be done by a double bond having the lowest number
• $$\begin{gathered} {\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{CH}={\mathrm{CH}}_2 \\ 54321 \end{gathered}$$:
• Hence, the root word is pent and the suffix is $-1-$ene. so pentene. There are no locants in this compound.
• So, the IUPAC name of ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{CH}={\mathrm{CH}}_2$ is Pent$-1-$ene.