Why is it generally inefficient to use a primary alkyl halide as an electrophile in a Friedel-Crafts alkylation?Select answer from the options belowPrimary alkyl halides do not form a sigma complex after a nucleophilic attack since they connect at the primary carbocation site.The use of a primary alkyl halide in a Friedel-Crafts alkylation reaction violates one of the three standard limitations for Friedel-Crafts alkylation reactions.Primary alkyl halides give primary carbocations which can rearrange beforfe being attacked by the aromatic ring, resulting in a mixture of products.Primary alkyl halides are resonance-stabilized, making them unreactive.
Question
Why is it generally inefficient to use a primary alkyl halide as an electrophile in a Friedel-Crafts alkylation?Select answer from the options belowPrimary alkyl halides do not form a sigma complex after a nucleophilic attack since they connect at the primary carbocation site.The use of a primary alkyl halide in a Friedel-Crafts alkylation reaction violates one of the three standard limitations for Friedel-Crafts alkylation reactions.Primary alkyl halides give primary carbocations which can rearrange beforfe being attacked by the aromatic ring, resulting in a mixture of products.Primary alkyl halides are resonance-stabilized, making them unreactive.
Solution
The correct answer is: Primary alkyl halides give primary carbocations which can rearrange before being attacked by the aromatic ring, resulting in a mixture of products.
This is because primary carbocations are less stable than secondary or tertiary carbocations. Therefore, they are more likely to undergo rearrangement to a more stable carbocation before the aromatic ring can attack. This can lead to a mixture of products, making the reaction inefficient.
Similar Questions
What is the correct order of steps in the mechanism for a Friedel-Crafts alkylation (after the initial formation of the reactive electrophile, E+)?Select answer from the options belowProton Transfer: Nucleophilic Attack: Loss of a Leaving GroupNucleophilic Attack: Proton TransferProton Transfer: Nucleophilic AttackProton Transfer: Nucleophilic Attack: Proton Transfer
The reaction given below is an example of Firedel craft alkylation reaction.In number of cases of Friedel – crafts alkylation the final product is found to contain a rearranged alkyl group. Generally with stronger Lewis acid product is rearranged due to enough polariazation of complex while with weak Lewis acid no such effect is observed. Temperature also favoures rearranged product.What is electrophile in give reaction?
In the proton transfer step of a Friedel-Crafts alkylation reaction, where does the proton go?Select answer from the options belowTo the aluminum trichloride, restoring a proper valence shellTo the ring to restore aromaticityTo form an acid byproduct (HX)To the sigma complex
In the proton transfer step of a Friedel-Crafts alkylation reaction, where does the proton go?Select answer from the options belowTo the aluminum trichloride, restoring a proper valence shellTo form an acid byproduct (HX)To the sigma complexTo the ring to restore aromaticity
Why do alkenes prefer to undergo electrophilic addition reaction while arenes prefer electrophilic substitution reactions? Explain.
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