Transition-Metal-Free One-Pot Synthesis of Naphthoquinonefuran Derivatives Through Sequential Nucleophilic Substitution-Nucleophilic Addition Reaction

J Org Chem. 2020 Jul 17;85(14):9313-9320. doi: 10.1021/acs.joc.0c00513. Epub 2020 Jul 1.

Abstract

A transition-metal-free route for tandem one-pot synthesis of naphthoquinonefuran derivatives from 2-hydroxynaphthoquinones has been developed. The sequentially accomplished process comprises an intermolecular alkynylation of sp2-carbon at the 3 position of 2-hydroxynaphthoquinones with arylethynyl bromides, followed by a base-promoted intramolecular nucleophilic annulation reaction. A broad range of functional groups is compatible with this reaction, and diverse naphtho[2,3-b]furan-4,9-diones can be obtained with good yields and excellent regioselectivity.