As an experiment, we first reacted acetaminophen with NaOH to deprotonate it at the alcohol position and create a good nucleophile. We then added iodo-butane for a SN2 reaction to occur and create 4-butoxyacetanilide.
One side reaction is the creation of butanol via SN2 attack of the NaOH at the electrophilic carbon.
My question is: How can we prevent the butanol side reaction from occurring?
My suggestion: when mixing NaOH and acetaminophen originally to create the nucleophilic oxygen use an excess of acetaminophen. Next, extract the ionized acetaminophen (with the anionic nucleophilic oxygen) with water and then react the extracted solution, ideally containing no NaOH because it's all reacted and only ionized acetaminophen, with the iodo-butane.
Problem: is this even possible? I'm not sure if the acetaminophen and ionized acetaminophen actually have different even solubility properties to be separated in this way?!
Is there another way to prevent butanol as a side product?
Thank you!!