Synthesis of naphthalenic melatonin receptor ligands

A highly efficient and versatile synthetic approach to the synthesis of nap hthalenic analogs of melatonin, compound 7, and its 2-alkyl substituted ana log 8 is described. This approach features the novel synthesis of substitut ed l-naphthyl acetonitrile 12 and 19 by nucleophilic addition of LiCH2CN to substituted 1-tetralone, followed by aromatization via a 2-step reaction s equence, dehydrogenation with DDQ and TsOH catalyzed dehydration.