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1028 CHAPTER 24 
 
24.24. 
(a) Upon treatment with excess methyl iodide in the 
presence of silver oxide, all of the OH groups are 
converted into methoxy groups, as shown: 
 
 
 
(b) Upon treatment with excess methyl iodide in the 
presence of silver oxide, all of the OH groups are 
converted into methoxy groups, as shown: 
 
(c) Upon treatment with excess methyl iodide in the 
presence of silver oxide, all of the OH groups are 
converted into methoxy groups, as shown: 
 
 
 
 
 
 
 
24.25. Under acidic conditions, the anomeric OH group can be protonated, giving an excellent leaving group (water). 
Loss of the leaving group generates a resonance-stabilized cation intermediate. 
 
 
 
This intermediate can then be attacked by ethanol, giving an oxonium ion, which is then deprotonated to give an acetal: 
 
 
 
 
 
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