Discussion In this experiment, anthracene and maleic anhydride were reacted in solution to produce a single organic product in crystal form. Anthracene is composed of a 3 carbon rings where the first ring has a 3 pi bonds while the other two has 2. Also, the double bonds are separated by single sigma bonds, which conjugate the double bond. Maleic anhydride has a five-membered ring with ring’s oxygen atoms bonded to two acyl group, ester R-COO. The abundant of esters, which serves as the electron withdrawal group, propels the effectiveness of this reaction. In the present case, the central ring of the anthracene possesses the characteristic properties of a diene, electron-rich, system [1]. Thus, this aromatic compound reacts with the 9 and 10 positions of the maleic anhydride dienophile, electron-poor, by 4 +2 cycloaddition [1]. 9 and 10 are the position of preference because it is where new bonds can be made without destroying the aromatic formation of the other two rings. This reaction results in a six-membered ring bridged on the 9 and 10 positions of anthracene. It is important to point out that this reaction is reversible, it is usually best carried out at the lowest possible temperature consistent. …show more content…
If the theory is considered, the carbonyl substituent can be oriented either directly under the diene to form the endo product or away from the diene to form the exo product. However, in practice, the endo product is the major product [2]. The transition state leading to the endo product allows more interaction between the electron-rich diene and the electron- withdrawing substituent on the dienophile, an energetically favorable arrangement