Efficient and Green Preparation of 2-Amino-4H-chromenes by a Room-Temperature, Na2CO3-Catalyzed, Three-Component Reaction of Malononitrile, Benzaldehydes, and Phloroglucinol or Resorcinol in Aqueous Medium

The preparation of substituted 2-amino-4H-chromenes by a Na2CO3-catalyzed reaction of malononitrile, benzaldehydes, and phloroglucinol or resorcinol in aqueous medium and at room temperature is reported. The merits of this procedure include limited use of organic solvents, easy workup technique, and high purity of products. The 2-amino-4H-chromenes were prepared in yields of 54-96%.