Final answer:
The question is about the halogen addition reaction mechanism of cyclohexene with bromine to form dibromocyclohexane. It involves a bromonium ion intermediate and follows with a backside attack by a bromide ion to yield the final product.
Step-by-step explanation:
The question deals with the reaction mechanism of cyclohexene with bromine to form dibromocyclohexane, which is a type of halogen addition reaction. In this mechanism, the double bond in cyclohexene acts as a nucleophile and attacks a bromine molecule (Br2). This results in the formation of a bromonium ion intermediate, where both bromine atoms are attached to the cyclohexane ring but one of them carries a positive charge. This intermediate is then attacked by a bromide ion (Br-), which comes from the bromine molecule that was polarized and broken in the first step. This attack occurs from the opposite side of the bromonium ion, leading to the final product, dibromocyclohexane. The reaction takes place in a solvent like CCl4 at a low temperature to stabilize the intermediate and to prevent any side reactions.
Remember that when drawing mechanisms, curved arrows are used to denote the movement of electrons, starting from the electron pair donor (nucleophile) to the acceptor (electrophile). Charges should also be indicated appropriately, negatively charged on the nucleophile and positive charges on electrophilic intermediates such as the bromonium ion.