To prepare 7-hydroxy-4-methyl Coumarin from Resorcinol by green technique (Pechmann Condensation)

Aim: To prepare and submit 7-hydroxy-4-methyl Coumarin from Resorcinol by green technique (Pechmann Condensation).

REQUIREMENT: Ethyl acetoacetate, resorcinol, pipette, measuring cylinder.

THEORY: Resorcinol reacts with ethyl acetoacetate in the presence of concentrated sulphuric acid to form 7-hydroxy-4-methyl Coumarin.

PROCEDURE:

• Dissolve 1.1g resorcinol in 1.35g of ethyl acetoacetate in a 50ml dry round bottom flask.
  
• Add 1.5g K10-montmorilonite clay to the mixture & mix thoroughly by a glass rod.
• Finally reaction mixture is appeared as paste..
• Heat on hot water bath for 3-4 hours
• Cool the reaction mixture at room temperature.
• Extract the 7-hydroxy-4-methyl Coumarin with ether by vigorous shaking.
• Separate the clay by filtration through Whatman Grade 4 filter paper.
• Separate the ether for 2 times.
• Evaporate the filtrate and product is found as a white solid.

FACTOR: The yield of 7-hydroxy-4-methyl Coumarin was 1.5g and M.P. was 188-190ºC.

USES: Coumarin and its derivative are examples of anticoagulant agents. They are widely used to present coagulation of blood under certain medical condition.

RESULT: The yield of obtained product was found to be ___ and percentage yield was ___ and M.P. was found to be ___ .

REFERENCE: Furniss B., Hannaford A., Smith P., Tatchell A., "Vogel's textbook of practical organic chemistry", 5th edition,