Question

please write hypothesis and purpose of experiment multistep reaction if you cant please dont write anything thank you

262 Part Three Properties and Reactions of Organic Compounds 32 EXPERIMENT 32 Multistep Reaction Sequences: The Conversion of Benzaldehyde to Benzilic Acid Green chemistry Multistep reactions Thiamine-catalyzed reaction Oxidation with nitric acid Rearrangement Crystallization Computational chemistry (optional) This benzaldehyde. In Experiment 32A, benzaldehyde is converted t a thiamine-catalyzed reaction. This part of the experiment dem "sreen" reagent t demonstrates multistep synthesis of benzilic aci can be utilized in organic chemistry. In Experi

Answer 1

The Conversion of Benzaldehyde to Benzillic acid

This is a multistep and multicomponent reaction in which more than one component is used in order to lead the conversion of reactants into the products. Intermediates and transition states also appears in the multistep reaction. The overall rate of the reaction can be determined from the slowest step.

Here Benzaldehyde is getting converted to Benzillic acid in 3 elementary steps in which the product of one step is the reactant of the other step.

o HNO3 Thi arnune 2. он hy drouhlon de benzeun) но go OH

The above reaction sequence can be explained in following steps -

1. Appropriate amount of thiamine chloride is taken in a round bottomed flask containing water . After that ethanol is being added as a solvent and the mixture was cooled at 273K.

2. In agitated solution of thiamine chloride was added the benzaldehyde and NaOH solution was also added into it . The reaction mixture was heated for 90 min at 333K.

3. The reaction mixture was cooled down naturally and ice bath crystallization process took place for the formation of crystals of Benzoin.

4. Benzoin and nitric acid was heated in a boiling tube and then it was recrystallized with ethanol. the product was benzil.

5. Correct amount of KOH in water was taken and added into benzil and condensed it till blue color appears. After that it was cooled down and washed with water and after that acidify with HCl to neutrlize the any alkali present.