Chapter 7, Problem 44P

Interpretation Introduction

Interpretation:

Thestructures of two different alkyl bromides both of which yield the indicated alkene as the exclusive product of $\text{E2}$ elimination are to be determined.

Concept introduction:

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The alkyl halides in presence of a strong base undergo dehydrohalogenation and form the corresponding alkene.

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In dehydrohalogenation $\text{H}$ and $\text{X}$ (halogen atom) areeliminated from adjacent carbons.

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The elimination of primary alkyl halides proceeds through $\text{E2}$ mechanism.

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In $\text{E2}$ mechanism, the attack of base and detachment of leaving group occurs simultaneously, and there is no carbocation formation step.

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According to Zaitsev rule, themost substituted alkene is the major product.