Draw the products of the following reactions. If the products can exist as stereoisomers, show which stereoisomers are formed.
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Verified step by step guidance

1. Analyze the given reaction: The starting material is a cyclohexene derivative, and the reagent is bromine (Br₂) in dichloromethane (CH₂Cl₂). This indicates a halogenation reaction, specifically an electrophilic addition to the double bond.
2. Understand the mechanism: Bromine reacts with the double bond in the cyclohexene ring via an electrophilic addition mechanism. The π-electrons of the double bond attack the bromine molecule, forming a bromonium ion intermediate.
3. Determine the stereochemistry: The bromonium ion intermediate is formed on the same plane as the cyclohexene ring. Bromine ions (Br⁻) then attack the bromonium ion from the opposite side (anti-addition), leading to trans stereochemistry in the final product.
4. Identify the product: The double bond in the cyclohexene ring is replaced by two bromine atoms, one on each carbon of the former double bond. The product is a dibromocyclohexane derivative with trans stereochemistry.
5. Draw the stereoisomers: Since the addition is anti, the bromine atoms will be on opposite sides of the ring (one above the plane and one below the plane). Ensure the stereochemistry is clearly represented in the drawing.

Key Concepts

Electrophilic Addition

Electrophilic addition is a fundamental reaction mechanism in organic chemistry where an electrophile reacts with a nucleophile, typically involving alkenes or alkynes. In this case, bromine (Br2) acts as the electrophile, adding across the double bond of the aromatic compound. This process results in the formation of a more stable product, often leading to the generation of stereoisomers due to the formation of chiral centers.

Stereoisomerism

Stereoisomerism refers to the phenomenon where compounds have the same molecular formula and connectivity but differ in the spatial arrangement of atoms. In the context of the reaction shown, the addition of Br2 can lead to the formation of different stereoisomers, such as enantiomers or diastereomers, depending on the arrangement of the bromine atoms around the newly formed chiral centers. Understanding stereoisomerism is crucial for predicting the properties and reactivity of the products.

Regioselectivity

Regioselectivity is the preference of a chemical reaction to yield one structural isomer over others when multiple possibilities exist. In the halogenation of the aromatic compound shown, regioselectivity will determine where the bromine atoms add to the double bond. This concept is essential for predicting the major products of the reaction and understanding how the structure of the starting material influences the outcome of the reaction.