How is aspirin synthesized from phenol?
The salicylic acid reacts with acetic anhydride in presence of sulphuric acid to form acetylated salicylic acid and acetic acid. Therefore, we can convert phenol to aspirin by treating phenol with sodium hydroxide and carbon dioxide in an acidic medium. Then treated the product salicylic acid with acetic anhydride.
How do you check the presence of phenolic compounds in the synthesis of aspirin?
The crude product and the purified product can be tested using ferric chloride. Ferric chloride forms highly colored complexes with phenolic compounds. So when the ferric chloride is added to the product, one can tell if the product mixture contains any of the starting material by the color of the solution.
How aspirin is synthesized?
Aspirin is prepared by chemical synthesis from salicylic acid, through acetylation with acetic anhydride. The molecular weight of aspirin is 180.16g/mol. It is odourless, colourless to white crystals or crystalline powder.
Is aspirin made from phenol?
The key compound in the synthesis of aspirin, salicylic acid, is prepared from phenol by a process discovered over 100 years ago by the German chemist Hermann Kolbe.
How is phenol converted to aspirin acid?
How can phenol be
- Conversion of phenol to Aspirin is done in two steps. Step1. First, phenol is converted to Salicylic acid by the following reaction:
- Step2. Salicylic acid on acetylation( introducing acetyl group –COCH3) using acetic anhydride produces Aspirin.
What type of reaction is the synthesis of aspirin?
The synthesis of aspirin is known in organic chemistry as an esterification reaction. This is a substitution reaction in which an alcohol (the –OH group in salicylic acid) reacts with acetic anhydride to form an ester, aspirin.
Does aspirin test positive for phenol?
No, because the aspirin does not have a phenol group. The ferric chloride gives a violet color with any molecule possessing a phenol group. Aspirin can irritate the stomach.
Why is sulfuric acid used in aspirin synthesis?
The purpose of adding sulphuric acid (catalyst) is to aid and augent the process of detaching the acetate ion (CH3COO–) from acetic anhydride which ultimately gets associated with H+ ion from phenolic hydroxy group in salicylic acid to be eliminated as a mole of acetic acid. Aim: To prepare aspirin from salicylic acid.
What is synthetic aspirin made of?
In fact, the starting material for the chemical synthesis of aspirin is benzene, derived from petroleum. This is then converted to phenol which in turn is converted to salicylic acid which is then converted to acetylsalicylic acid or ASA, which we know as aspirin.
What is phenol in aspirin?
Aspirin is also known as acetylsalicylic acid. Phenol is treated with NaOH to produce phenoxide ion. Phenoxide ion then undergoes electrophilic substitution with CO2 to yield salicylic acid as the major product. This is called kolbe’s reaction. Then, acetylation of Salicylic acid produces Aspirin as a major product.
How will you convert phenol into picric acid I aspirin?
When phenol is treated with hot conc. nitric acid in the presence of conc. sulphuric acid yellow coloured picric acid is produced. The reagent used to convert phenol into picric acid is concentrated nitric acid.
What is the catalyst used to prepare the aspirin?
To prepare aspirin, salicylic acid is reacted with an excess of acetic anhydride. A small amount of a strong acid is used as a catalyst which speeds up the reaction. In this experiment, sulfuric acid will be used as the catalyst. The excess acetic anhydride will be quenched (reacted) with the addition of water.
What is synthesis of aspirin?
Synthesis of Aspirin. After the synthesis of aspirin, the product was recrystallized for purification to rid the product of impurities. A major impurity that could be found in the crude product would be unreacted salicylic acid. The crude product and the purified product can be tested using ferric chloride.
What is the phenol group in aspirin?
A phenol group is distinguished as the -OH that is coming off a ring system. If iron chloride is added to a reactant containing a phenol group, the solution would turn purple. Aspirin does not contain a phenol group, however, salicylic acid, contains a phenol group.
Why is acetic acid used in the synthesis of aspirin?
Therefore during the synthesis of the aspirin some of the aspirin will be converted back to starting material. To help push the reaction toward the products, one could distill off the acetic acid. This is because the reduction of the products will cause more starting material to react to regain equilibrium.
What are the sources of error in the synthesis of aspirin?
One possible source of error is in the nature of the reaction of aspirin. These carbonyl reactions are all equilibrium reactions which means it is impossible for the reaction to go to 100% completion. Therefore during the synthesis of the aspirin some of the aspirin will be converted back to starting material.