For the following alkyne, draw the product(s) when it reacts with Cl₂ (2 equiv.).

It has been possible to synthesize lactones (cyclic esters) by electrophilically adding I―Cl to an alkyne. Draw the plausible mechanism for this reaction of cyclization.

For the given alkyne, determine the product(s) when it undergoes halogenation reaction (with 1 equiv. Br ₂).

For the addition of Br₂ and Cl₂ to alkynes, trans addition is highly favored. However, more of the syn addition product is produced with chlorination. Justify this fact.

For the addition of 1 mole of bromine to 1 mole of 2-butyne, which one of the following is a better approach to the reaction?

Draw the mechanism for the reaction of 3-hexyne with one equivalent of Cl₂.