Organocatalytic asymmetric Friedel-Crafts alkylation/cascade reactions of naphthols and nitroolefins

The asymmetric Michael-type Friedet-Crafts reaction of naphthols and nitroolefins promoted by bifunctional thiourea-tertiary amine organocatalysts (up to 95% ee) was investigated; on simply extending the reaction time further cascade reactions could occur to generate enantiopure dimeric tricyclic 1,2-dihydronaphtho[2,1-b]furanyl-2-hydroxylamine derivatives.