Under Cr2O7^2-/H+ distillation, oxidation of a primary alcohol yields which product?

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Multiple Choice

Under Cr2O7^2-/H+ distillation, oxidation of a primary alcohol yields which product?

When a primary alcohol is oxidized with a strong oxidant in acidic solution, the usual path is to go from alcohol to aldehyde, then, if the reaction continues, to a carboxylic acid. Introducing distillation changes the outcome: the aldehyde that forms is typically volatile enough to be distilled off as it forms, removing it from the oxidizing environment. This stops further oxidation, so the product isolated is the aldehyde rather than the carboxylic acid. That’s why the aldehyde is the best choice here. A ketone would come from a secondary alcohol, not a primary one, and a carboxylic acid would require the aldehyde to remain in the reaction mixture and be oxidized further. An unoxidized alcohol isn’t the product from this oxidation under these conditions.

When a primary alcohol is oxidized with a strong oxidant in acidic solution, the usual path is to go from alcohol to aldehyde, then, if the reaction continues, to a carboxylic acid. Introducing distillation changes the outcome: the aldehyde that forms is typically volatile enough to be distilled off as it forms, removing it from the oxidizing environment. This stops further oxidation, so the product isolated is the aldehyde rather than the carboxylic acid.

That’s why the aldehyde is the best choice here. A ketone would come from a secondary alcohol, not a primary one, and a carboxylic acid would require the aldehyde to remain in the reaction mixture and be oxidized further. An unoxidized alcohol isn’t the product from this oxidation under these conditions.

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