Why alkynide alkylation reaction shown below fails to yield the desired product? What actual major product would be formed in this reaction?

Provide a reaction scheme for the synthesis of trans-non-4-ene using acetylene as the starting material.

Provide a reaction sequence showing how the following target molecule can be prepared from the starting material.

CH₃CH₂CH₂CH₂Cl → CH₃CH₂CH₂CH₂CH₂CH₂CH₃

Propose the synthesis of the following molecule starting with acetylene.

Propose a synthesis of the given molecule from ethylene.

Draw the synthesis of (Z)-5,5-dimethyl-1-phenylhex-2-en-1-ol from benzaldehyde and other reagents.

Show a sequence of steps to show how the target molecule can be prepared using the provided starting material.