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A unique ketone to allylic alcohol rearrangement has been discovered in the 7-phenylmorphinan-6-one system. The rearrangement is catalyzed by boron tribromide. Its mechanistic pathway is postulated to involve the coordination of the carbonyl group by boron tribromide, which would consequently promote migration of the axial 7-beta-phenyl group.

The Diels-Alder reaction of opiate dienophiles with o-quinodimethanes is a route to tetrahydronaphthalene-fused opiates. This was gleaned from an examination of the Diels-Alder reactions of thebaine and a related opiate with the reactive diene, which led to the synthesis of tetrahydronaphthalene-fused opiates that are not easily available using other means. The 6-methoxy group of thebaine is also found to play a key role in the reaction.

By reacting lithium enolate of hydrocodone with commercially available diphenyliodonium iodide (DII), the conversion of hydrocodone into 7-phenylhydrocodone can be obtained in good amount. The DII approaches the beta-face of the enolate, resulting in enolization and epimerization of the 6-beta isomer, which is then ketonized to the stable 6-alpha epimer.

Selenium group transfer chemistry was used for a stereospecific synthesis of pseudocodeine. The previous approach, wherein codeine is converted to its 6(beta)-chloro derivative and the latter subjected to S(sub N)2 displacemnt in aqueous acetic acid, produces a mixture of isomers where separation of codeine is cumbersome. The stereospecific route involving selenium intermediates proved to have higher yield and better efficiency as it facilitated purification.