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Bromination Of E-Stilbene Lab Report

794 Words4 Pages

In this experiment, the bromination of E-Stilbene, or trans 1, 2 diphenylethene was performed in order to figure out whether the cation intermediate in the mechanism was cyclic or acyclic. The hypothesis was that if the product of the reaction was 100% meso- 1,2-dibromo-1,2-diphenylethane, or meso-stilbene dibromide, the intermediate was cyclic, but if there was a 50:25:25 ration of meso, D, and L isomers, the intermediate was acyclic. In the mechanism with the cyclic intermediate, the pi electrons in the E-Stilbene double bond attack the bromine molecule, causing heterolytic cleavage, resulting in the formation of a bromide ion, and a cyclic structure on the E-Stilbene where a bromine atom forms partial bonds with both the carbons involved in the double bond. This cyclic structure provides steric hindrance on one side of the E-Stilbene molecule. The bromide ion then attacks one of the carbons in the double bond, forming a bond with that carbon, and causing the other bromine atom to form a bond with the opposite carbon, resulting in the …show more content…

However, due to the hindrance from the cyclic structure, the bromide ion is only able to attack from the side opposite that of the cyclic structure. Since the cyclic structure can form on either side of the double

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