Question

How will you convert benzaldehyde to cinnamic acid?

Answer 1

by carbonyl condensation

Answer 2

The Perkin reaction by rctn with an ethanoic anhydride and an ethanoate salt.

or

First step: Add CH2(CO2Et)2 along with Na+-OEt and ethanol to benzaldehyde. (carbonyl condensation)

Second step: Add H3O+.

The Perkin reaction is an organic reaction developed by William Henry Perkin that can be used to make cinnamic acids i.e. α-β-unsaturated aromatic acid by the aldol condensation of aromatic aldehydes and acid anhydrides in the presence of an alkali salt of the acid several reviews have been written. The reaction of phenylacetic acid and benzaldehyde with triethylamine and acetic anhydride to alpha-phenylcinnamic acid is an example of this reaction type.