Microwave-Assisted One-Pot Synthesis of 2-Amino-2-chromenes Using Piperazine as a Catalyst Under Solvent-Free Conditions

A simple and efficient procedure for the synthesis of substituted 2-amino-2-chromenes employing one-pot three-component condensation reaction of aromatic aldehydes with malononitrile and activated phenols has been developed by using the odorless and easy to work piperazine in the absence of solvents under microwave irradiation. The present method is operationally simple and offers several advantages such as high yields, short reaction time, and simple workup.