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What is the mechanism for the electrophilic addition of hydrogen bromide to propene? Include the step-by-step process and the stereochemistry of the product.

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The electrophilic addition of hydrogen bromide  HBr  to propene  C3H6  is a two-step process that involves the formation of a carbocation intermediate. The mechanism is as follows:Step 1: Protonation of the alkeneIn the first step, the alkene  propene  acts as a nucleophile and attacks the electrophilic hydrogen atom of the HBr molecule. This results in the breaking of the H-Br bond, with the electrons from the bond moving to the bromine atom. Consequently, a carbocation intermediate is formed, and a bromide ion  Br-  is generated as a leaving group.Propene: CH3-CH=CH2HBr: H-BrCH3-CH=CH2 + H-Br  CH3-CH + -CH3 + Br - Step 2: Nucleophilic attack by the bromide ionIn the second step, the bromide ion  Br-  acts as a nucleophile and attacks the carbocation intermediate, specifically the positively charged carbon atom. This leads to the formation of the final product, 2-bromopropane.Carbocation intermediate: CH3-CH + -CH3Bromide ion: Br - CH3-CH + -CH3 + Br -   CH3-CH Br -CH3Stereochemistry of the product:The electrophilic addition of HBr to propene results in the formation of 2-bromopropane. Since the reaction proceeds through a carbocation intermediate, there is no specific stereochemistry involved in this reaction. The product formed is a single achiral molecule, and there is no formation of enantiomers or diastereomers.In summary, the electrophilic addition of HBr to propene involves the protonation of the alkene to form a carbocation intermediate, followed by the nucleophilic attack of the bromide ion to generate the final product, 2-bromopropane. The product has no specific stereochemistry as it is an achiral molecule.
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