Protoberberine ausReissert-Verbindungen, 5. Mitt.: Synthese des (±)-Bharatamins

摘要

Alkylation of theReissertcompound1by methyl 2-bromomethylbenzoate (2) followed by spontaneous intramolecular cyclization affords dibenzo a,gquinolizinone4which in turn can be reduced to benzyl ether5by LiAlH4/NaBH4. Debenzylation of5by ethanolic HCl furnishes the title compound6in improved total yield.