Which sequence of reagents would be expected to accomplish the synthesis of 1-butyne shown below? A) 1. H₂O/H₂SO₄, HgSO₄ cat.; 2. H₂, Pt B) 1. HBr; 2. H₂, Pt; 3. NaOH C) 1. H₂, Lindlar catalyst; 2. BH₃•THF; 3. H₂O₂, NaOH D) 1. HBr, peroxides; 2. NaOH; 3. H₂, Pt E) 1. O₃ 2. H₂O

Question

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The synthesis of 1-butyne requires the conversion of a terminal alkyne, which is accomplished with a Lindlar catalyst (Pd/CaCO3) to give the cis alkene. The cis alkene is then treated with BH3-THF to give the anti-Markovnikov alcohol. Finally, the alcohol is dehydrated with H2SO4 and heat to give the alkyne. Option C is the only sequence of reagents that matches this process. Option D is incorrect because peroxides would cause the formation of a mixture of products instead of the desired product. Option A is incorrect because both steps are reduction reactions instead of oxidative reactions, and option B is incorrect because NaOH cannot be used to convert an alcohol to an alkyne. Option E is incorrect because the sequence of reagents does not involve the necessary reduction and dehydration steps.

Which Sequence of Reagents Would Be Expected to Accomplish the Synthesis