Catalytic hydration of olefins is the primary process used in their creation, though a student might be more familiar with their manufacture via the dehydration of alcohols.
Codeine is simply the addition of a methyl and this functional group to morphine.  They often form azeotropes and when reacted with Lewis acids give oxonium salts. In the presence of oxygen this class of compounds can oxidize into unstable peroxides, resulting in an explosion.  Catalytic hydration of olefins is the primary process used in their creation, though a student might be more familiar with their manufacture via the dehydration of alcohols. FTP, name this class of organic compounds characterized by an oxygen bonded between two carbons.
Codeine is simply the addition of a methyl and this functional group to morphine.  
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