Question

When Br2 and H2O react with an alkene to generate a bromohydrin, which stereochemical course does the mechanism take? a. Anti addition to give the trans product. b. Syn addition to give the cis product. c. Anti addition to give the cis product. d. Syn addition to give the trans product.

Answer 1

Answer:

a. Anti addition to give the trans product.

Explanation:

First the alkene and Br₂ react and form an intermediate bromonium ion, which is highly reactive. This bromonium ion then reacts with water, which attacks from the opposite site of the Br atom (this is an anti addition). Thus the in the final product the hydroxide ion and the bromine are in opposite sides (this is the trans product).