DDQ Oxidation of 6- or 8-Allyl-7-hydroxycoumarins. A New Synthesis of Benzodipyrandiones and Furobenzopyranones

Article abstract of DOI:10.1246/bcsj.65.1191

A novel synthesis of 2H,8H-benzo<1,2-b:3,4-b'>dipyran-2,8-diones, 2H,8H-benzo<1,2-b:5,4-b'>dipyran-2,8-diones, 2H-furo<2,3-h><1>benzopyran-2-ones, and 7H-furo<3,2-g><1>benzopyran-7-ones was achieved by developing 2-pyrone and furan ring over coumarin. 6- or 8-Allyl-7-hydroxycoumarins on oxidation with 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) afforded benzodipyrandiones and furobenzopyranones.The structures of the compounds now synthesized were established by analytical, spectral, and comparison with authentic samples prepared by the known procedures.