aDpto. de Química Orgánica, Universidad de Almería, 04120 Almería, Spain
Abstract:
The natural dihydrobenzofuran neolignan 1 and its derivative 3 have been prepared through intramolecular C–H insertion catalyzed by a Rh(II) chiral complex. Moderate diastereo and enantioselectivities were observed. The cis and trans diastereomers were separated and unambiguously identified. The absolute configurations of the major isomers were established through chiral HPLC analysis and study of the Cotton effects in their circular dichroism curves.