One-pot four component synthesis of 1h-pyrazolo [1,2-b]phthalazine-5,10-dione derivatives using calcined mg-fe hydrotalcite catalyst

A simple, efficient and One-pot four component synthesis to afford the library of 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives using novel heterogeneous calcined Mg-Fe-CO3 hydrotalcite at room temperature is described. The calcined hydrotalcite with a Mg/Fe ratio of 3:1 derived from calcinations at 500°C was found to be a suitable catalyst that gives best catalytic activity for this reaction. Hydrotalcites are non-toxic, easy to separate and the isolated catalyst was reused for a number of times without loss of catalytic activity. Hence, making this process green and benign.