Question 31.17 - Organic Chemistry

Question

Locate the isoprene units in each compound.

a.

b.

Step-by-Step Solution

Answer

Answer

a. 

b.

Step-by-Step Solution Step 1: Isoprene units

Isoprene units are a carbon chain containing five carbon atoms and C-C double bonds. One isoprene unit has a formula ${\mathbf{CH}}_{\mathbf{2}}\mathbf{=}\mathbf{C}\left({\mathrm{CH}}_3\right)\mathbf{-}\mathbf{CH}\mathbf{=}{\mathbf{CH}}_{\mathbf{2}}$ . For example, diterpenoids have four isoprene units.

Step 2: Isoprene units in α - pinene

A $\mathrm{\alpha }-\mathrm{pinene}$ is a monoterpene having two isoprene units and is shown as:

                                            Isoprene units in $\mathrm{\alpha }-\mathrm{pinene}$

Step 3: Isoprene units in humulene.

A humulene is a sesquiterpene having three isoprene units and is shown as:

Isoprene units in humulene