Controllable synthesis of pyrazolo[3,4-b]pyridines or substituted malononitrile derivatives through multi-component reactions in ionic Liquid

Article abstract of DOI:10.1071/CH08290

A multi-component reaction of aldehyde, malononitrile, and 5-amino-3-methyl-1-phenylpyrazole was carried out smoothly in [bmim][BF ₄] without any added catalyst. Through this reaction, pyrazolo[3,4-b]pyridines or substituted malononitrile derivatives were obtained conveniently and controllably at different temperatures. The ionic liquid used can be easily recovered and efficiently reused for at least five runs.