Methylamine reacts with bromoethane by nucleophilic substitution to produce a mixture of products - AQA - A-Level Chemistry - Question 32 - 2021 - Paper 3

To determine the correct answer, we need to analyze the possible products formed by the nucleophilic substitution of methylamine with bromoethane.

1. Methylamine Structure: Methylamine (CH(_3)NH(_2)) has one methyl group and can potentially react with bromoethane (C(_2)H(_5)Br) as a nucleophile.

2. Possible Products: The nucleophilic substitution can lead to several products:

   • A: C(5)H({12})NH(_2) represents the tertiary amine with expansion from the two-carbon bromoethane molecule.
   • B: (C(_2)H(_5))NCH(_3) indicates the formation of ethylmethylamine, a valid product.
   • C: [(C(_2)H(_5))N(CH(_3))]Br(^-) implies the formation of a quaternary ammonium compound, which is not possible under typical conditions unless the amine becomes a quaternary structure after further reactions which is not described in the question context.
   • D: [(C(_2)H(_5))N(CH(_3))]Br(^-) is similar to C and represents the same product.

3. Conclusion: Since C is dependent on the structure suggesting an unstable quaternary amine as a product, the answer is:

C: [(C(_2)H(_5))N(CH(_3))]Br(^-) is not a possible product of this reaction.