Multistep Synthesis Lab Report

Explanation of the Multistep Synthesis of Benzilic Acid
The synthesis of several complex organic compounds follows a multistep synthesis. "Multistep synthesis" refers to the procedure in which the product of one reaction serves as the starting material in the subsequent reaction. The multistep synthesis of benzilic acid begins with a conversion benzaldehyde to benzoin through a condensation reaction. The benzoin then oxidizes into benzil, which undergoes rearrangement to give benzilic acid.
Benzoin Synthesis * When two benzaldehyde molecules condense in the presence of thiamine, it leads to the formation of a molecule of benzoin. The thiamine behaves as a coenzyme catalyst. This step of the reaction involves the addition of ethanol and sodium hydroxide into an aqueous solution of thiamine hydrochloride and creating a reaction with pure benzaldehyde. When you heat this mixture to a temperature of 60 degrees Celsius for about 90 minutes and then cool it in an ice bath, the benzoin crystallizes out. Recrystallization of these crystals from hot ethanol yields pure benzoin as a colorless powder.
When you heat benzoin with concentrated nitric acid using a reflux condenser, evolution of reddish brown nitrogen dioxide occurs and then stops. When you add cold water to the cooled reaction mixture, benzil precipitates out as a yellow solid. You can then recrystallize this substance from hot