1,4-Disulfopiperazine-1,4-diium chloride ([Piper-(SO3H)2].2Cl) as an efficient ionic catalyst for synthesis of phthalazine derivatives

This article describe the applicability of 1,4-disulfopiperazine-1,4-diium chloride ([Piper-(SO3H)2].2Cl) as a green, versatile and Brönsted acidic ionic catalyst in the promotion of the synthesis of phthalazine derivatives via one-pot three component reaction between aromatic aldehydes, 1,3-diketone derivatives and phthalhydrazide under solvent-free reaction conditions. The main advantages of this method are: (1) simplicity of the procedure, (2) solvent-free conditions, (3) availability of the starting materials, (4) high reaction rates and excellent yields, (5) reusability of the catalyst and (6) no column chromatographic of the products.