What is obtained in this reaction?

Question

CH3CH2CH=CH2 + Cl2 --->
1-butene + chlorine

Answer 1

CH3CH2CH=CH2 + Cl2 ---> CH3CH2CHCl-CH2Cl

1,2-dichlorobutane

Answer 2

Technically this reaction depends on the solvent.
In non-nucleophilic solvents (traditionally CCl4 was used), the product in this case is 1,2-dichlorobutane.
When water is the solvent, the product is 1-chloro-2-butanol.
When an alcohol is used, the product is 1-chloro-2-alkoxybutane. For example, in methanol the product is 1-chloro-2-methoxybutane.
Why the difference:
Both reactions precede through a transition state in which the double bond (nucleophile) is attacking the chlorine (electrophile) molecule. This creates a transition state which has one Cl atom forming bonds to both of the carbons of the double bond, and breaking the bond to the other Cl atom. This puts a partial positive charge on the carbons of the double bond.
In an alcohol solvent, the alcohol does a nucleophilic attack on one of the carbons that is bound to Cl. It attacks the more substituted one, since it bears more positive charge. This places the OR group at C2 and leaves the Cl still connected to C1.
When there is no alcohol solvent, the chloride ion formed by breaking of the Cl-Cl bond is the best nucleophile in solution, and will do the same thing that the alcohol does.

Answer 3

1 chloro - butane