Question

1
CH3 and
Reaction between neopentyl bromide CH3 | H3C-C-CH2Br
ethanol gives 2-ethoxy-methylbutane as the major products because ?
(A) this involves a 1, 2-
hydride shift
(B) this involves a 1,2 -
alkyl shift
(C) this occurs through a
Sn1 mechanism
(D) this is also
accompanied with the
formation of alkenes
as by product​

Answer 1

Reaction between Neopentyl bromide and  Ethanol to give  2-ethoxy-2-methylbutane as the major product

Explanation:

Option (b): this involves a 1,2 - alkyl shift

Neopentyl bromide reacts with ethyl alcohol to form 2-ethoxy 2-methyl butane.

1. Neopentyl bromide (a primary alkyl halide) undergoes heterolytic cleavage of carbon- bromine bond to form bromide ion and a primary carbocation.
2. This primary carbocation undergoes 1,2-methyl shift and gets converted to more stable tertiary carbocation.
3. This tertiary carbocation is attacked by ethoxide nucleophile.
4. This intermediate looses a proton and forms 2-ethoxy 2-methyl butane. Hydrogen bromide is also formed as a by-product.