No abstract

No abstract

Boron tribromide is presented as a highly reactive reagent that simultaneously allows the demethylation and fully diastereoselective cyclization of different precursor molecules, obtained by an aldol‐type reaction, to a series of hydroxylated aryldihydrobenzofuran systems in racemic form. The latter are often found as key structures in natural compounds of different classes. Syntheses of educts, which mainly took advantage of a versatile Rieche formylation, are also described.

Organic chemistryOrganic chemistry Z 0200 Putrescine, Spermidine, Spermine, and Related Polyamine Alkaloids -[528 refs.]. -(BIENZ, S.; DETTERBECK, R.; ENSCH, C.; GUGGISBERG, A.; HAUSERMANN, U.; MEISTERHANS, C.; WENDT, B.; WERNER, C.; HESSE, M.; Alkaloids (Academic Press) 58 (2002) 83-338; Org.-Chem. Inst., Univ. Zuerich, CH-8057 Zuerich, Switz.; Eng.) -Lindner 30-284