Elimination vs substitution: 2-bromopropane treated with sodium ethoxide in ethanol yields what major product?

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Elimination vs substitution: 2-bromopropane treated with sodium ethoxide in ethanol yields what major product?

When a secondary alkyl halide is treated with a strong base in a protic solvent, elimination (E2) often dominates over substitution because the bulky carbon centers hinder backside attack needed for SN2, while the base can readily remove a beta hydrogen to form a double bond. Here, sodium ethoxide pulls a beta hydrogen from 2-bromopropane, the electrons form the C=C bond, and bromide leaves, yielding propene. The alternative substitution path would give an ether (isopropyl ethyl ether) but is less favorable under these conditions due to steric hindrance and the strong basic environment, so the major product is propene.

When a secondary alkyl halide is treated with a strong base in a protic solvent, elimination (E2) often dominates over substitution because the bulky carbon centers hinder backside attack needed for SN2, while the base can readily remove a beta hydrogen to form a double bond.

Here, sodium ethoxide pulls a beta hydrogen from 2-bromopropane, the electrons form the C=C bond, and bromide leaves, yielding propene. The alternative substitution path would give an ether (isopropyl ethyl ether) but is less favorable under these conditions due to steric hindrance and the strong basic environment, so the major product is propene.

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