Deep Eutectic Mixture Catalyzed One-Pot Three-Component Synthesis of 1H-pyrazolo and 2H-indazolo Phthalazines

A direct, simple and green protocol describes synthesis of 1H-pyrazolo[1,2-b] phthalazine-5,10-diones and 2Hindazolo[ 2,1-b] phthalazine-triones derivatives using deep eutectic mixture (choline chloride: malonic acid) as a homogeneous catalyst as well as solvent at reflux temperature. This method provides significant advantages such as short reaction time, easy workup, and high yield of product, atom economy and recyclability of catalyst. Keywords: Aldehydes, aqueous medium, deep eutectic mixture, 2, 3-dihydrophthalazine-1, 4-dione, 5, 5-dimethylcyclohexane- 1, 3-dione, ethylcyanoacetate, malononitrile.