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What is the mechanism of the acid-catalyzed cleavage of an ether and how does it differ from the base-catalyzed cleavage of an ether? Provide a step-by-step explanation of the mechanism using a specific example.

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The acid-catalyzed cleavage of an ether involves the breaking of the C-O bond in the ether molecule under acidic conditions, while the base-catalyzed cleavage of an ether involves the breaking of the C-O bond under basic conditions. The mechanisms of these two reactions differ in the way the C-O bond is broken and the intermediates formed during the reaction.Let's use the example of diethyl ether  CH3CH2-O-CH2CH3  for both mechanisms.Acid-catalyzed cleavage of an ether:1. Protonation: In the presence of a strong acid  e.g., HCl , the oxygen atom in the ether molecule gets protonated, forming a protonated ether  CH3CH2-OH+-CH2CH3 .2. Nucleophilic attack: A nucleophile  e.g., Cl-  attacks one of the carbon atoms bonded to the oxygen, breaking the C-O bond and forming a new C-Cl bond. This results in the formation of an alkyl halide  CH3CH2-Cl  and an alcohol  CH3CH2-OH .3. Deprotonation: The alcohol formed in the previous step gets deprotonated by a base  e.g., water  to regenerate the acid catalyst, resulting in the final products: an alkyl halide and an alcohol.Base-catalyzed cleavage of an ether:1. Nucleophilic attack: In the presence of a strong base  e.g., OH- , the base acts as a nucleophile and attacks one of the carbon atoms bonded to the oxygen in the ether molecule. This leads to the formation of an alkoxide intermediate  CH3CH2-O-CH2CH2-OH .2. Proton transfer: The alkoxide intermediate abstracts a proton from a nearby water molecule, resulting in the formation of an alcohol  CH3CH2-OH  and an alkoxide ion  CH3CH2-O- .3. Nucleophilic substitution: The alkoxide ion acts as a nucleophile and attacks another ether molecule, breaking the C-O bond and forming a new C-O bond. This results in the formation of an alcohol and an ether with one less carbon atom  CH3-O-CH2CH3 .In summary, the acid-catalyzed cleavage of an ether involves protonation, nucleophilic attack, and deprotonation steps, while the base-catalyzed cleavage of an ether involves nucleophilic attack, proton transfer, and nucleophilic substitution steps. The intermediates formed during the reaction are also different, with a protonated ether in the acid-catalyzed mechanism and an alkoxide intermediate in the base-catalyzed mechanism.
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