FORMATION OF BENZOFURAN AND 2H-CHROMENE STRUCTURES IN ONE REACTION - A NOVEL SYNTHESIS OF 2H-CHROMENE DERIVATIVES

Heating the morpholinal of nitrosalicylic aldehyde with methyl propiol ate in acetonitrile in the presence of CuI affords an equimolar mixtur e of thoxycarbonylmethyl-3-morpholino-5-nitrobenzofuran and -methoxyca rbonyl-2-morpholino-6-nitro-2H-chromene, the structures of which were determined by X-ray analysis. Only the 2H-chromene mentioned above was obtained in the absence of CuI and solvent.