To synthesis and submit phenytoin from benzil by using microwave oven method.

 Experiment

Synthesis of Phenytoin from Benzil by Microwave Irradiation

Aim:

To synthesis and submit phenytoin from benzil by using microwave oven and calculate its percentage yield. 

Requirements:

Chemicals Required:

Benzil = 1.25g

Urea = 0.75g

NaOH (30%)= 3.75 ml

Methanol = 18.75 ml 

Glassware: breaker, funnel,glass rod, pipette etc

Instrument: Microwave oven

Theory:

Principle:

The microwave region of Electro Magnetic spectrum light between IR irradiation and frequency corresponding to the wavelength of 1cm-1to 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. 

Phenytoin is prepared by condensation of benzil and urea under reflux condensation to give heterocyclic compound Pinnacol. When the pinnacol is treated with sodium hydroxide it’s rearrangement to produce phenytoin as 

sodium salt and the esterification gives phenytoin as crude product. This reaction is completed to take place only 2 to 3 minutes microwave irradiation. 

Synthesis Reaction of phenytoin:

Procedure:

◆ 1.25gm of benzil, 0.75gm urea, 3.75ml 30% sodium hydroxide and 18.75 ml methanol was taken in a beaker and kept in a Microwave oven for 3 minutes. 

◆Then it was cooled to room temperature and 50ml of water was poured, mixed well and filtered. 

◆To the filtrate con. HCl, was added to get the crude product. 

◆Then the product was recrystallized from ethanol.

Melting Point:

 295℃ to 298℃

Use of Phenytoin:

Anti-convulsant 

Result:

Phenytoin was synthesised and reported the following

1. Theoretical yield =

2. Practical yield =

3. Percentage yield =