Formation and Disproportionation of Xanthenols to Xanthenes and Xanthones and Their Use in Synthesis

Base-Promoted Divergent Annulation of Conjugated Ynones and Methyl 2-(Cyanomethyl)benzoates to Access 1-Naphthols and Xanthones

A facile and efficient base-mediated divergent annulation of methyl 2-(cyanomethyl)benzoates and conjugated ynones has been described. A broad range of 1-naphthols and xanthones were formed in moderate to excellent yields. The notable features of this protocol include readily available precursors, broad substrate scope, complete regioselectivity, and substrate-controlled divergent synthesis. The gram-scale preparation and synthetic transformations of the resulting 1-naphthols and xanthones demonstrate their utility.

Oxidation of BINOLs by Hypervalent Iodine Reagents: Facile Synthesis of Xanthenes and Lactones

Xanthene derivatives have broad applications in medicines, fluorescent probes, dyes, food additives, etc. Therefore, much attention was focused on developing the synthetic methods to prepare these compounds. Binaphthyl‐based xanthene derivatives were prepared through the oxidation of BINOLs promoted by the hypervalent iodine reagent iodosylbenzene (PhIO). Nine‐membered lactones were obtained through a similar oxidative reaction when iodoxybenzene (PhIO₂) was used. Additionally, one‐pot reactions of BINOLs, PhIO and nucleophiles such as alcohols and amines were also investigated to provide alkoxylated products and amides in good to excellent yields.