acetylation or diacetylation of certain opioids

[Solipsis]

Alright, so you not only acetylate but it also ceases to be a 6,7-dihydromorphinone? Did not realize that was possible.

 

[sekio]

Ketones and "ene-ols" are tautomeric, that is, they interconvert. The equilibrium favours the ketone form by a factor of 1000 or so, but you can still drive a reaction with it.

This is also what drives some enolate (carbonyl additions) and aldol chemistry.

So I guess very technically, it's no longer a dihydromorphinone, but it would hydrolise right back to one. Analogy: hydrolysis of thebacon to hydrocodone. (Only carbonyls with alpha hydrogens can become an enol though, there are always exceptions)