Which sequence of reactions is expected to produce the product below as the final, and major, organic product? A) 1. Br₂, CCl₄ 2. H₂, Lindlar's cat. B) 1. H₂, Lindlar's cat.; 2. Br₂ C) 1. Br₂, CCl₄ 2. Na, NH₃(l) D) 1. Na, NH₃(l); 2. Br₂ E) 1. Br₂, CCl₄ 2. H₂, Pt

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Quizplus · Accepted Answer

The product shown is an alkyne, suggesting that the reaction sequence involves converting a terminal alkyne to the product. This can be achieved by first reducing a terminal alkyne using Lindlar's catalyst to form a cis-alkene. The cis-alkene can then be converted back to a terminal alkyne by treatment with a strong base, such as Na in NH3(l). Finally, the terminal alkyne can be brominated to produce the desired alkyne product. Therefore, the correct sequence would be 1. H₂, Lindlar's cat.; 2. Br₂.

Which Sequence of Reactions Is Expected to Produce the Product