Which of the following sequence of reagents is most suitable for the conversion of 1-propyne into trans-2-hexene?

Step-by-step solution

Step 1: 1-propyne reacts with the strong base NaNH ₂ to deprotonate the terminal alkyne, forming the propynide ion. Step 2: The propynide ion undergoes an S_N2 reaction with n-propyl bromide ( CH ₃ CH ₂ CH ₂ Br ) to form a 6-carbon internal alkyne, 2-hexyne. Using isopropyl bromide would lead to a branched alkyne or elimination. Step 3: To obtain trans-2-hexene, the internal alkyne (2-hexyne) must be reduced using Birch reduction ( Na in liquid NH ₃ ). Lindlar catalyst would yield the cis-alkene, and H ₂/ Pd-C woul