Model Route to 5-Bromo-3,4-dihydro-4-hydroxy-7,9,10-trimethoxy-1,3-dimethyl-1H-naphtho[2,3-c]pyran: A Potential Precursor to Extended Quinones

Abstract

A protocol has been developed for the synthesis of the linear naphthopyran 16, by the TiCl₄-catalyzed isomerization of 2,5-dimethyl dioxolane 1, having a methoxy group at position 1′ and a bromine atom at position 4′ of the naphthyl precursor to favor isomerization at position 2′.

Keywords:

• Isomerization
• naphthopyranquinones
• naphthopyrans
• naphthyldioxolanes

ACKNOWLEDGMENT

The authors thank the Cape Peninsula University of Technology and the Cannon Collins Trust for financial assistance.