Question

i performed the brominationnof trans-stilbene by mixing transtilbene, a brominating agent and chloroform. what is the purpose of chloroform in this experiment. also what is the purpose of the air condenser in bromination?

Answer 1

The bromination of trans-stilbene using bromine (Br₂) in chloroform take place with elctrophilic addition of Br⁺ to the double bond to form bromonium ion intermediate which was attacked by nucleophile Br^- to get the desired product as 1,2-dibromo-1,2-diphenylethane in good yield.

The chloroform is used as the solvent for the reaction which is having polar in nature due to three chlorine bond with carbon therfore have good dipole moment . It will help to break the bond between two bromine atom to generate partial charge like  Br⁺ as electrophile and Br^- as nucleophile.

The purpose of the air condenser used in the reaction because bromine vapors irritate eyes, throat and are very toxic with inhalation. The bromine absorb through the skin and can damage the nervous system and the thyroid gland.

The detail product formation with reaction mechanism is explained in the below image.

Poge No Date *: Bre7 Br Chok Arsh addrdioo givs Trans hlbene meso pmatuo &Led +BY Bromonium aH Rudepale bt Anti diloame Compuu