9. Alkenes and Alkynes

What is the major product of the reaction of 1 mol of propyne with each of the following reagents?

j. the product of part i followed by 1-chloropropane

What is the major product of the reaction of 1 mol of propyne with each of the following reagents?

i. sodium amide

Show how you might synthesize the following compounds, using acetylene and any ­suitable alkyl halides as your starting materials. If the compound given cannot be ­synthesized by this method, explain why.

a. hex-1-yne

b. hex-2-yne

c. hex-3-yne

Give two sets of reactants (each set including an alkyl halide and a nucleophile) that could be used to synthesize the following alkyne:

CH₃CH₂C≡CCH₂CH₂CH₂CH₃

Show the products of the following acetylide alkylation reactions. [Make sure your product has the correct number of carbons.]

(a)

Show the products of the following acetylide alkylation reactions. [Make sure your product has the correct number of carbons.]

(c)

Ethinylestradiol is a synthetic hormone mimic used as a contraceptive for its ability to prevent ovulation. Suggest a mechanism for the synthesis using sodium acetylide and estrone, followed by quenching with acid.

Predict the product of the following acetylide alkylations.

(a)

Predict the product of the following acetylide alkylations.

(c)

Suggest reagents you might use to generate the product from the given reactant.

(a)

Suggest reagents you might use to generate the product from the given reactant.

(c)

A student provided the product of the following reactions, but made a mistake. Identify the mistake, correct the mistake, and suggest a way for the student to avoid that mistake in the future.

(b)

A student provided the product of the following reactions, but made a mistake. Identify the mistake, correct the mistake, and suggest a way for the student to avoid that mistake in the future.

(a)

In Chapter 10, you learned how to make an alkyne by acetylide alkylation with a 1° haloalkane. Suggest a mechanism by which this reaction occurs.