Here are the essential concepts you must grasp in order to answer the question correctly.
Grignard Reagents
Grignard reagents are organomagnesium compounds formed by the reaction of an alkyl or aryl halide with magnesium in an anhydrous ether. They are highly reactive and serve as nucleophiles in organic synthesis, allowing for the formation of carbon-carbon bonds. In this question, the formation of compound B from compound A illustrates the utility of Grignard reagents in building complex organic structures.
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Carbonation of Grignard Reagents
Electrophilic Addition Reactions
Electrophilic addition reactions involve the addition of an electrophile to a nucleophile, typically across a double bond. In the context of this question, the reaction of compound B with acetone demonstrates how a Grignard reagent can add to a carbonyl group, leading to the formation of a new carbon-carbon bond. Understanding this concept is crucial for predicting the products of the reactions described.
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Features of Addition Mechanisms.
Hydrogenation and Dehydrohalogenation
Hydrogenation is the process of adding hydrogen to unsaturated compounds, often using a catalyst, to convert alkenes or alkynes into alkanes. Conversely, dehydrohalogenation involves the elimination of hydrogen halides from alkyl halides to form alkenes. In this question, the hydrogenation of compound E to form isobutylcyclohexane and the decolorization of Br2 are key steps that illustrate these fundamental reactions in organic chemistry.
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The dehydrohalogenation mechanism.