Synthesis of Aspirin Assisted by Microwave Oven

Aim

To Prepare and Submit aspirin from Salicylic acid and Calculate the Percentage Yield.

Principle

The microwave region of Electro-Magnetic spectrum light between IR irradiation and frequency corresponding to the wavelength of 1cm-1 to 1m. The organic compound can be heated by applying energy in the form of microwave high-frequency IR irradiation. The use of this technique can have substantial saving time for laboratory synthesis of drugs and chemicals.
Aspirin is prepared from Salicylic acid, in this method salicylic acid reacts with acetic anhydride in the presence of sulphuric acid to form the crystalline nature of aspirin.

Reaction

Procedure

Two reactions consist of a two-neck flask with a magnetic stir bar, temperature, sensor and intensive cooler. A mixture of salicylic acid and acetic
anhydride is filled in the reaction flask and three drops of conc. Sulphuric Acid is added the apparatus is installed by means of a glass tube in the microwave system. Standard refluxing apparatus for microwave system. The reaction mixture is heated under stirring for 90 sec. with 900 W to 140 C, during the following cooling down the clear yellowish solidified to a compact white crystalline mass
Melting Point: 1350C
Use: Anti-inflammatory agent

Result

Aspirin was synthesised and reported the following

1. Theoretical yield =
2. Practical yield =
3. Percentage yield =