An unusual route for the regioselective acylation of polycyclic aromatic hydrocarbons: Nitrile oxide addition followed by isoxazoline degradation

By treatment with a base such as sodium methoxide or surprisingly lithium a luminium hydride monocycloadducts 1a-c afforded the corresponding oximes 2a -c which were oxidized to ketones 3a-c by the Dess-Martin method. The same ketones 3a-c are obtained by reductive ring opening of 1a-c with Raney-Ni. Monocycloadducts 1d-h also gave oximes 2d-h upon treatment with the same ba ses, but complex reaction mixtures were obtained when oximes 2d-h were subj ected to oxidation or monocycloadducts 1d-h were subjected to reduction wit h Raney-Ni.