Question

The neopentyl halide in ethanol yields alkenes by $E1$ mechanism due to

• A. low concentration of solvent
• B. absence of base
• C. it is a primary halide
• D. steric factor which prevents E2 mechanism
• E. solvation effect

Answer 1

Answer: (D)

$E1$ mechanism readily occur in $3^{\circ }$ carbocation. Presence of higher alkyl groups in alkyl halide also favours $E1$ mechanism.

The neopentyl halide in ethanol yields alkenes by $E1$ mechanism due to steric factor which prevents E2 mechanism. In $E1$ mechanism, Heterolytic dissociation of alkyl halide followed by abstraction of proton by base from a $C$ adjacent to the positively charged $C$ atom $(\beta -C$ atom $)$, takes place as follows: