2/13/2014
Diels Alder reaction of anthracene and Maleic anhydride
Reaction Scheme:
Figure one shows the reaction scheme for Diels Alder reaction of anthracene and maleic anhydride
Theory/Background:
The Diels-Alder reaction was created in 1928 by two German chemists Otto Diels and Kurt Alder (Wade, Jr., 2013). This reaction is best used for making six membered rings with different functional groups. The reaction is called a 4+2 cycloaddition because a ring is formed by four pi electrons in the diene interacting with two pi electrons of the alkene or alkyne (Wade, Jr., 2013). In this experiment anthracene was used as the diene and considered to be electron rich in the reaction. Maleic anhydride was the electron poor dienophile used in the reaction. The reaction converted two pi bonds into two sigma bonds forming 1,9 dihydroanthracene-9, 10-, succinic anhydride (Wade, Jr., 2013).
Procedure:
Step 1: Weighed 0.5g of anthracene and 0.25g of maleic anhydride
Step 2: Added 6mL of xylene
Step 3: Allowed the mixture to boil for 30 minutes
Step 4: Placed 6mL of xylene in ice bath
Step 5: Cooled down reaction to room temperature for 5 minutes and placed in ice bath for 5 minutes to recrystallize
Step 5: Collected crystals by vacuumed filtration
Step 6: Mixed 6mL of xylene with crystals and heated the mixture
Step 7: Allowed the mixture to cool to room temperature
Step 8: Cooled the solution in an ice bath for 5 minutes
Step 9: Collected the crystalized solid by vacuum filtration
Step 10: Measured the melting point for the crystalize solid
Reagent Table:
Table 1: The chemicals and properties used in the reaction
Compound
Quantity
Molar Mass
(g/mol)
Melting Point (C)
Boiling Point (C)
Anthracene
0.5g
178.23
216-218
340
Maleic Anhydride
0.25g
98.06
54-56
200
Potassium Bromide
100
119
63.38
759
Xylene
6mL
106.17
137-144
9,10 dihydroanthracene-9, 10-, succinic anhydride
276.23
262-264