N-methyl pyridinium-p-toluene Sulfonate (NMPyTs) catalyzed synthesis of pyrano[2,3-c]pyrazoles

Abstarct:A simple one-pot synthesis of pyrano[ 2,3-c]pyrazoles was developed by a three-component reaction of various benzaldehydes, malononitrile and 1-phenyl or hydro-3-methyl-1H-pyrazol-5(4H)-one in the presence of N-methyl pyridinium p-toluene sulfonate (NMPyTs) as a catalyst. All of the synthesized compounds were identified by IR, 1H NMR, 13C NMR and mass spectroscopy techniques. In the mentioned method, the use of thermal condition is avoided. The key advantages of this process are high yields, shorter reaction times, easy work-up, and purification of products by the non-chromatographic method. The synthesis of pyrano[2,3-c] pyrazoles using NMPyTs as an efficient catalyst is the novel methodology work.