An efficient basic alumina supported continuous flow synthesis of chromene derivatives

An efficient basic alumina supported continuous flow method was developed for the synthesis of various chromene derivatives by one-pot three component condensation of arylaldehydes, malononitrile and dimidone using basic alumina as solid supported catalyst under continuous flow. This protocol offer various advantages such as mild reaction condition, simple work-up procedure, avoids the usage of strong acid catalysts, re-usability of catalyst, and produces higher yields in shorter reaction time with high selectivity. Chromene derivatives were characterized by different spectral analysis such as IR, 1HNMR, 13CNMR, mass spectrometry and elemental analysis. [Display omitted]