Final answer:
Chemical synthesis often employs methoxy groups as protective groups, demonstrated in the synthesis of 1'-O-methylglycosidic analogues and retained in reactions such as methylation and coupling without enone formation. Methoxy groups can be kept intact throughout various synthetic steps, including radical chemistry.
Step-by-step explanation:
The student's question centers around the utilization of a methoxy group in radical chemistry without converting to an enone. In chemical synthesis, methoxy groups are often used to protect nucleophilic centers during reactions.
For example, in the formation of 1'-O-methylglycosidic protected analogues, chemoselective methylation is achieved using reagents like NaH and methyl iodide (MeI) to introduce a methoxy group that serves as a protecting group.
An example given is the conversion of a compound to its triazolide derivative followed by subsequent treatment to yield a cytidine derivative without eliminating the methoxy group to the enone.
Further, the O-methylation process is described where the oxygen atom acts as a nucleophile, indicating that methoxy groups can be kept intact through various synthetic steps.
Another mention is the use of methylboronic acid in coupling reactions, showing that methoxy groups can indeed partake in radical chemistry, such as in the synthesis of modified nucleosides for oligonucleotide assembly.
These examples highlight that the methoxy group can be both a protective group and participate in coupling reactions without necessarily leading to enone formations, aligning with the radical chemistry that retains the functional group through the reaction sequence.