Question

Suggest efficient syntheses of (E)- and (Z)-2-heptene from propane and any necessary alcohols or inorganic reagents. This means that not all of the carbon appearing in the final products originates with propane, but may come from the alcohol. You can use any reagents or solvents used for any standard organic reactions that we have covered in class. (basically anything organic chemistry 1)

Answer 1

Answer – We are given propane and we need to synthesis (E)- and (Z)-2-heptene. First we need to reacts propane with Br₂ in light and formed 2-bromopropane. This 2-bromopropane reacts with strong base t-ButONa and formed propene. Then this propene reacts with H₂O/H⁺ formed 2-propanol. Then this propanol gets oxidized and form ketone. This ketone reacted with strong base and from the enolate. This enolate reacted with butyl bromide and formed 2-heptanone. This 2-heptanone reacts with NaBH₄ as formed 2-heptanol. This 2-heptanol reacts with conc.H₂SO₄ and formed 2-heptene. This 2-heptene reacts with Br₂ in CCl₄ and formed 2,3-dibromoheptane. Then this reacted with strong base of 2 equivalent of NaNH₂ and formed 2-heptyne. This alkyne reacts with one time with Na/NH₃ from (E)-2-heptene and one time with H₂,Pd/C and formed (Z)-2-heptene. The all reaction showing the as follow -