Phosphine-Catalyzed Asymmetric (3+2) Annulations of δ-Acetoxy Allenoates with 2-Naphthols

Phosphine-catalyzed (3+2) annulations of delta-acetoxy allenoates with 2-naphthols are reported, wherein the delta C of allentoate reacts with the alpha C of 2-naphthol to form the C-C bond while a C-O bond is formed between the gamma C of allenoate and the hydroxyl group of 2-naphthol. When (R)-SITCP is used as the catalyst, 1,2-dihydronaphtho[2,1-b]furans are obtained in moderate to good yields and with high enantioselectivity. This method is useful for the construction of enantiomerically enriched atropoisomeric furans via a central to axial chirality conversion strategy.