A New Application of Mohr's Salt as a Cheap and Powerful Catalyst for Synthesis of Novel Pyranocoumarins

A new application of Mohr's salt (ammonium iron (II) sulfate hexahydrate) has been found in an organic reaction in which the Knoevenagel condensation, Michael addition, and intermolecular cyclization of 4-hydroxyxoumarin, malononitrile and aromatic aldehydes led to novel and known pyranocoumarins. Simple operation, use of readily accessible commercial starting materials, good to excellent yields and short reaction times show efficiency of this method for the synthesis of these biologically interesting products.