Benzaldehyde can be prepared by reacting phenyl magnesium bromide with A. N, N-dimethylformamide B. carbon dioxide C. formaldehyde D. ethyl chloroformate

N, N-dimethylformamide
carbon dioxide
formaldehyde
ethyl chloroformate

The correct answer is B. carbon dioxide.

Phenyl magnesium bromide is a Grignard reagent, which is a type of organometallic compound that reacts with carbon dioxide to form aldehydes. In this reaction, the Grignard reagent acts as a nucleophile and attacks the electrophilic carbon atom of carbon dioxide. The resulting intermediate is then protonated to form the aldehyde product.

The other options are incorrect because they do not react with phenyl magnesium bromide to form aldehydes.

  • N, N-dimethylformamide is a solvent that can be used in Grignard reactions, but it does not react with phenyl magnesium bromide to form aldehydes.
  • Formaldehyde is a reactant that can be used to form aldehydes, but it does not react with phenyl magnesium bromide.
  • Ethyl chloroformate is a reactant that can be used to form esters, but it does not react with phenyl magnesium bromide.