elimination vs substitution

Question

Strong bulky base (t-BuOK) acting on 2-bromobutane favors formation of:

RankGuru · Accepted Answer

1. **Base Nature**: Potassium tert-butoxide ($t-BuOK$) is a very strong but **bulky (sterically hindered)** base.
2. **Approach**: Due to its size, it cannot easily reach the more 'internal' $\beta$-hydrogen to give the more substituted alkene (Zaitsev product).
3. **Hydrogen abstraction**: It prefers to abstract the most accessible (less hindered) $\beta$-hydrogen from the terminal methyl group.
4. **Result**: This lead to the formation of **But-1-ene** (the **Hofmann product**) as the major product rather than But-2-ene.
5. **Note**: Standard bases like $EtO^-$ or $OH^-$ would favor the Zaitsev product (But-2-ene).

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elimination vs substitution

Select the correct option: