Question

Give the product for the reaction of 1-butene with methanol in the presence of acid. The mechanism is the same as the mechanism for the addition of water to alkenes.
(A) 1-butanol
(B) 1-methoxybutane
(C) 2-ethoxybutane
(D) 1-ethoxybutane
(E) 2-methoxybutane

Answer 1

Answer:

The final result is 2-methoxybutane.

Explanation:

1-butene has a carbon-carbon double bound between C1 and C2.

When it will react with methanol, in the presence of an acid, the result will be an ether.

C4H8 + CH3OH → C5H12O

An acid-catalyzed ether synthesis from alkenes is limited by carbocation stability.

In the first step, the double bound will disappear. The C2 atom will be a C+ atom, this becaus it has only 3 bounds and not 4.

This C+ -atom will atract the O- atom to form an ether. The CH3 of methanol will bind on the C3 atom, this is the most stable position.

2-methoxybutane will be formed. It has a structural formula of C5H12O

1-methoxybutane will not be formed, because it's less stable.

1-butanol will be formed when water is added to 1-butene. The mechanism has the same principle but not the same product.

1-ethoxybutane and 2-ethoxybutane have a structural formula of C6H14O, this will not be the final result.

The final result is 2-methoxybutane.