Several characteristics are desirable for a derivatization
reaction:
The reaction is reliable and proceeds to completion. Less
unreacted starting material will simplify analysis. Also, this
allows a small amount of analyte to be used.
The reaction is general, allowing a wide range of substrates,
yet specific to a single functional group, reducing complicating
interference.
The products are relatively stable, and form no degradation
products within a reasonable period, facilitating analysis.