Abstract
Synthesis of a key precursor 2-allyl-3-bromo-1,4-dimethoxynaphthalene (1) used in constructing various naturally occurring biologically active pyranonaphthoquinones is carried out utilizing easily available 1-methoxynaphthalene as a starting material. The synthesis was accomplished with Dakin's oxidation and Claisen rearrangement, thereby providing another easy approach toward (1) without involving highly lachrymatric 2-bromonaphthoquinone.
GRAPHICAL ABSTRACT
ACKNOWLEDGMENTS
We are grateful to S. G. Gupta for making the laboratory facilities available and to the Department of Science and Technology–Funding for Structure in Science and Technology (DST-FIST) for instrumentation support. R. A. L. thanks the University Grants Commission for providing a junior research fellowship and the Department of Chemistry, University of Pune, for spectral analysis. Thanks are also due to R. C. Chikate and V. B. Kumbhar for helpful discussions.