Question

Explain The Rosenmund Rxn ???​

Answer 1

$\huge\bf{Answer:-}$

• A deficiency of aldehyde produces alcohol, not ketone as suggested in your question.

• Aldehyde and ketone occupy the same oxidation level, and are separated simply by substitution on either side of the carbonyl.

• In this case, due to the mechanism, the chloride of acyl chloride is replaced by hydrogen - an additional carbon-containing group Who will bear the kiton has no opportunity to include.

Answer 2

Explanation:

$\huge\mathtt\pink{Rosenmund \:Rxn}$

Rosenmund Reduction Mechanism explains the way acyl chlorides are selectively reduced into aldehydes. Karl Wilhelm Rosenmund first reported this reaction in 1918, thus the reaction was named after him. The Rosenmund reaction is a hydrogenation process where molecular hydrogen reacts with the acyl chloride in the presence of catalyst – palladium on barium sulfate. The barium sulfate reduces the activity of the palladium due to its low surface area, thereby preventing overreduction. Should the need for further reduction in palladium activity arise (as in the case of more reactive acyl chlorides), a poison can be added to totally deactivate the palladium catalyst.

Common poisons used to limit palladium activity in the Rosenmund technique are thioquinanthrene and thiourea. The need for deactivation arises because the subsequent aldehyde formed from the reduction of the acyl chloride will also be reduced to a primary alcohol by the system. This primary alcohol would then react with the remaining acyl chloride, forming an ester. The Rosenmund catalyst (palladium on barium sulfate) is prepared by the reduction of palladium(II) chloride solution with reducing agent formaldehyde in the presence of barium sulfate.