The synthesis and chemistry of functionalized furochromones.4. Addition of nitronate anions to 3-bromochromone and 6-bromofurochromone. An expedient route to furo(3',2':6,7)-benzopyrano(2,3-d)-isoxazolones and chromono(2,3-d)isoxazolones

Article abstract of DOI:10.1016/S0040-4039(00)91842-2

Addition of nitronate anions to 3-bromochromone 1 and 6-bromofurochoromone 2 results in the efficient generation of 3-hydroxy-2-(1-(hydroxyimino)alkyl,aryl or carboalkoxy) substituted chromones and the corresponding 6,7-disubstituted furochromones. These