9. Alkenes and Alkynes

Long, polarized bonds are also reducible in the same way that the C―C π bond of an alkyne is. Show a mechanism by which a C―Br bond might be reduced by sodium metal.

What are products of the following reactions?

c.

Show how you would convert

a. oct-3-yne to cis-oct-3-ene.

b. pent-2-yne to trans-pent-2-ene.

Predict the product of the multistep synthesis

Answer Problem 39, parts a–h, using 2-butyne as the starting material instead of propyne.

h. H₂/Lindlar catalyst

Answer Problem 39, parts a–h, using 2-butyne as the starting material instead of propyne.

g. excess H₂, Pd/C

What are products of the following reactions?

b.

What are products of the following reactions?

a.

What stereoisomers are obtained from the following reactions?

b.