Polyethylene glycol (PEG‐400) Mediated One‐pot Green Synthesis of 4,7‐Dihydro‐2 <i>H</i> ‐pyrazolo[3,4‐ <i>b</i> ]pyridines Under Catalyst‐free Conditions
Nagaraju Kerru, Lalitha Gummidi, Suresh Maddila, Sreekantha B. Jonnalagadda
Abstract
Abstract Polyethylene glycol (PEG‐400) was proved a highly efficient and green solvent reaction medium for the synthesis of series of novel 3,6‐dimethyl‐4,7‐dihydro‐2 H ‐pyrazolo[3,4‐ b ]pyridine derivatives with excellent yields by a three‐component reaction of 1 H ‐pyrazol‐3‐amino‐5‐methyl, various aromatic or heteroaromatic aldehydes and chosen CH‐active compounds under catalyst‐free conditions via one‐pot strategy. This transformation is compatible with a broad diversity of functional group tolerance. Rapid synthesis, mild reaction conditions, high yields, no catalyst or column chromatography, cost‐effectiveness and green solvent are the benefits of this protocol.