Question

What products are formed from monochlorination of (2r)−2−bromobutane at c1 and c4? draw the products using skeletal structures?

Answer 1

From monochlorination of (2R)−2−bromobutane at C1 is formed (2S)-2-bromo-1-chlorobutane.

From monochlorination of (2R)−2−bromobutane at C4 is formed (2R)-3-bromo-1-chlorobutane.

According to Cahn-Ingold-Prelog rules, the priority of halogen substituents decreases in the following sequence:

-I > -Br > -Cl > -F

According to the rule, chlorine has priority over bromine, so the configuration changes at C1 substitution.