Catalytic hydrogenation of the isomeric homoproaporphines (5a and 5b) and the deuterated dienones (6a and 6b) in the presence of platinum catalyst afforded the same mixture of cyclohexanols (7a and 7b). In contrast, reduction of hydrochloride of 5a on palladium-charcoal provided the cyclohexanone (8a) while that of 5b gave a mixture of the cyclohexanone (8b) and the cyclohexenone (9).
