Synthetic studies on morphine-based analgesics: an approach to angular substitution in 4a-aryldecahydroisoquinolines via dienolate chemistry

The reaction of the dienolate generated from 9 using lithium hexamethyldisilazide with a range of alkyl halides has been explored and the regioselectivity and stereochemistry of the adducts determined. Reaction of the dienolate with an oxaziridine gave hydroxylation at the C-8a position as found in some potent morphine-like analgesics.