CHEM 322aL Lecture Notes - Lecture 3: Syn And Anti Addition, Alkene, Halonium Ion
Document Summary
For syn and anti addition, you can consider the following pictures to add x and y. Then, plug the groups of the alkene into the wedges and dashes. Back ones (h, h) on the other side. Draw them in a tetrahedral structure on each carbon. Me rotate to have the alkene plan perpendicular to the paper. Syn and anti addition depends on mechanism, and mechanism dictates the type of addn: when an alkene makes a cyclic bromonium ion, the nucleophile comes from the backside to make an anti addn. Oh: when you can make a tertiary carbocation from a bromonium ion, it makes an acyclic tertiary carbocation instead of a cyclic bromonium ion. Then, the nucleophile adds to the carbocation on both sides, resulting in both syn and anti addn. Here is the list of reactions and their types of addn. As a representative of halogen, i am using bromine herein.
