8-Methoxy-1-tetralone was synthesized in a concise and efficient manner involving a sequential palladium-mediated cross-coupling reaction (Heck), catalytic hydrogenation, and intramolecular acylation mediated by Eaton’s reagent or Lewis acids. The pivotal step in the synthesis was the use of a bromine substituent at the benzenoid C4 position of the intermediate methyl 4-arylbutyric ester to ensure cyclization ortho to the methoxy moiety and obviate cyclization at the para position to the thermodynamically preferred 6-methoxy-1-tetralone, the sole product obtained in the absence of this blocking group.
Key words
8-methoxy-1-tetralone - Eaton’s reagent - Heck reaction - intramolecular acylation - Lewis acids