A multicomponent synthesis of 2-amino-3-cyanopyridine derivatives by carbon-based solid acid catalyst

The interesting biological properties of pyridines derivatives have promoted a great deal of research effort toward development of new synthetic methodologies for 2-amino-3-cyanopyridines and their derivatives [1, 2]. In continuation of our research on solid acid synthesis [3], here we wish to report a simple and efficient method forthe one-pot synthesis of 2-amino-3-cyanopyridines in excellent yields using a catalytic amount of starch-derived carbon based solid acid. The synthesis of sulfonated carbon-based solid acid nanocatalyst (SCP-SO3H) has been investigated through the one-step hydrothermal reaction of Starch as carbohydrate source and ptoluenesulfonic acid as sulfonating in the presence of citric acid (Scheme). The application of SCP-SO3H was investigated in the synthesis of 2-amino-3- cyanopyridines via the condensation of aldehydes, acetophenone, malononitrile and ammonium acetate. A variety of ketones and aldehydes was used to afford the corresponding products in good to excellent yields