Intramolecular Oxidative Coupling of Aromatic Compounds. VI. An Efficient Synthesis of Some Dibenzocyclooctene Lignans

Abstract

The 1,4-diaryl-2,3-dimethylbutanes (4) and (5) were readily prepared by reductive coupling of an arylacetone precursor followed by hydrogenation. Intramolecular oxidative coupling (dichlorodicyanobenzoquinone/trifluoroacetic acid) gave dibenzocyclooctene derivatives in good yield. (±)-Deoxyschizandrin and the corresponding trans isomer, existing in two distinct conformations, were prepared.