Question

Question: Solved Problem 9-1 showed the synthesis of dec-3-yne by adding the hexyl group first, then the ethyl group. Show the reagents and intermediates involved in the other order of synthesis of dec-3-yne by adding the ethyl group first and the hexyl group last.

Short answer

Being a strong base and nucleophile, acetylide ion can substitute halide from an alkyl halide, followed by the formation of substituted alkyne. For reaction, the substrate group should be a primary alkyl halide.

Step-by-step solution

Alkylation of acetylide ions 

Being a strong base and nucleophile, acetylide ion can substitute halide from an alkyl halide, followed by the formation of substituted alkyne. For reaction, the substrate group should be a primary alkyl halide.

Synthesis of dec-3-yne by adding ethyl and hexyl groups 

The synthesis of dec-3-yne can be done by adding ethyl and hexyl groups to acetylide ions. The addition of ethyl group first with the acetylide ion forms but-3-yne

Then the further addition of hexyl group forms dec-3-yne.