19. Reactions of Aromatics: EAS and Beyond

Predict the major product from the Birch Reduction

Predict the major product from the Birch Reduction

Predict the major products of the following reactions.

(d) p-xylene + Na (liquid NH3, CH3CH2OH)

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A common illicit synthesis of methamphetamine involves an interesting variation of the Birch reduction. A solution of ephedrine in alcohol is added to liquid ammonia, followed by several pieces of lithium metal. The Birch reduction usually reduces the aromatic ring (Section 17-14C), but in this case it eliminates the hydroxy group of ephedrine to give methamphetamine. Propose a mechanism, similar to that for the Birch reduction, to explain this unusual course of the reaction.

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Propose mechanisms for the Birch reductions of benzoic acid. Show why the observed orientation of reduction is favored in each case.

α-Tetralone undergoes Birch reduction to give an excellent yield of a single product. Predict the structure of the product, and propose a mechanism for its formation.

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