Question

Question: 2-Pentylcinnamaldehyde, commonly called flosal, is a perfume ingredient with a jasmine-like odor. Flosal is an $\mathit{\alpha }\mathbf{,}\mathit{\beta }$-unsaturated aldehyde made by a crossed aldol reaction between benzaldehyde $\left(C_6{H}_{5}CHO\right)$and heptanal $\left(C{H}_{3}C{H}_{2}C{H}_{2}C{H}_{2}C{H}_{2}C{H}_{2}CHO\right)$, followed by dehydration. Draw a stepwise mechanism for the following reaction that prepares flosal.

Short answer

Answer

Step-by-step solution

Conversion of aldehyde to alkene

Two reactions used to convert the aldehyde into alkene are Wittig reaction and ozonolysis.

Mechanism of the reaction

In the first step of the reaction, hydroxide ion abstracts the alpha hydrogen and creates a nucleophilic center.

This attacks on the carbonyl carbon and gets attached to it. The protonation takes place and the alpha hydrogen is abstracted by hydroxide ion. The charge shifts to form double bond and results in the formation of a flosal compound.

The mechanism is shown below:

Mechanism of the reaction