The presence of the pyridine ring system in a number of natural products, vitamins, and pharmacologically significant molecules [1] has made it a prime target for scientific research. In particular, 2-amino-3,5-dicarbonitrile-6-thio-pyridines exhibit diverse pharmacological activities and are useful as anti-prion [2], anti-hepatitis B virus [3], and anti-cancer [4] agents. These compounds are generally synthesized via one-pot three-component condensation of an aldehyde, malononitrile and a thiol in the presence of several catalysts such as DABCO or triethylamine [5], piperidine [6], DBU [7], etc. However, some of these methodologies encounter some limitations, such as long reaction times, unsatisfactory yields, harsh reaction conditions, requirement of expensive catalysts and hazardous organic solvents. Herein we wish to report a green and rapid methodology for the synthesis of 2-amino-3,5- dicarbonitrile-6-thio-pyridines by one-pot multi-component reaction of a variety of aryl aldehydes with malononitrile and thiophenol in ionic liquid [bmim]Br as an efficient promoting medium without the use of any catalyst.

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