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Design a synthesis pathway for the production of 2-butyne from 1-bromobutane, including all necessary reagents and reaction mechanisms.

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To synthesize 2-butyne from 1-bromobutane, we can follow these steps:1. Formation of 1-butyne from 1-bromobutane via double dehydrohalogenation.2. Conversion of 1-butyne to 2-butyne using isomerization.Step 1: Formation of 1-butyne from 1-bromobutane1-bromobutane can be converted to 1-butyne through a double dehydrohalogenation reaction. This involves two E2 elimination reactions.Reaction 1: First E2 eliminationReagents: NaNH2  sodium amide  in liquid ammonia  NH3 Mechanism: The strong base NaNH2 abstracts a proton from the -carbon, and the electrons from the C-H bond form a double bond with the -carbon, while the leaving group  Br-  departs.1-bromobutane + NaNH2 -> 1-butyne + NaBr + NH3Reaction 2: Second E2 eliminationReagents: NaNH2 in liquid ammonia  NH3 Mechanism: The strong base NaNH2 abstracts a proton from the -carbon, and the electrons from the C-H bond form a triple bond with the -carbon, while the leaving group  Br-  departs.1-butyne + NaNH2 -> 1-butyne + NaBr + NH3Step 2: Conversion of 1-butyne to 2-butyne using isomerizationReagents: H2SO4  sulfuric acid  and HgSO4  mercuric sulfate Mechanism: The reaction proceeds via a keto-enol tautomerization. The terminal alkyne proton is first abstracted by the acid, and the resulting carbocation is attacked by water. The intermediate enol then undergoes keto-enol tautomerization to form the more stable 2-butyne.1-butyne + H2SO4 + HgSO4 -> 2-butyneOverall synthesis pathway:1-bromobutane + 2 NaNH2 -> 1-butyne + 2 NaBr + 2 NH31-butyne + H2SO4 + HgSO4 -> 2-butyne

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