Protecting Groups: How They Work. Protecting Groups: Alcohol Alkylation Alcohol Groups do not “Survive” Many Organic Reactions Alkylation (Ether Formation)

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Protecting Groups: How They Work

Protecting Groups: Alcohol Alkylation Alcohol Groups do not “Survive” Many Organic Reactions Alkylation (Ether Formation) Protects OH’s During Synthesis Can Remove the Protecting Group w/ Dilute Aqueous Acid Generally Dissolve Alcohol in Acid, THEN add Isobutylene Addition in this Manner Minimizes Isobutylene Dimerization Let’s See Why We Might Want to Use a Protecting Group

Protecting Groups: Silyl Ethers Silyl Ethers Stable Over a 4-12 pH Range (Acidic and Basic) Can Survive Conditions of Many Organic Reactions Typically Removed w/ Flouride Source (NBu 4 F; aka TBAF) Silyl Ethers More Volatile Than Alcohols (GC Applications)