Multistep Reaction Sequences The Conversion of Benzaldehyde to Benzilic Acid

Multistep Reaction Sequences The Conversion of Benzaldehyde to Benzilic Acid 

Green chemistry Multistep reactions Thiamine-catalyzed reaction Oxidation with nitric acid Rearrangement Crystallization 

The experiment demonstrates multistep synthesis of benzilic acid starting from benzaldehyde. In Experiment 32A, benzaldehyde is converted to benzoin using a thiamine-catalyzed reaction. This part of the experiment demonstrates how a green reagent can be utilized in organic chemistry. In Experiment 32B, nitric acid oxidizes benzoin to benzil. Finally, in Experiment 32C, benzil is rearranged to benzilic acid. The scheme on the next page shows the reactions. 

Heating and Cooling Methods, Sections 6.1-6.3 Reaction Methods, Sections 7.1-7.4 Filtration, Section 8.3 

Although this experiment is intended to illustrate a multistep synthesis to the students, each part may be done separately, or two out of the three reactions can 

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