Question

Locate the isoprene units in each compound.

a.

b.

Short answer

Answer

a.

b.

Step-by-step solution

Step-by-Step SolutionStep 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.

Isoprene units in α-pinene

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

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

Isoprene units in humulene.

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

Isoprene units in humulene