One-Pot Syntheses of 2H-Indazolo[2,1-B] Phthalazine-Triones Catalyzed by Ionic Iiquid
A simple and efficient one-pot method for the preparation of 2H-indazolo [2,1-b] phthalazine-triones from phthalhydrazide, dimedone and aromatic aldehydes has been developed using ionic liquids as catalysts. Two ionic liquid catalysts are described, and the ionic liquid [(CH2)4SO3HMIM]HSO4 catalyst is found to be more effective than [HMIM]HSO4 for this condensation reaction.
Xiaoming Qian and Huawu Liu
F. Yang et al., "One-Pot Syntheses of 2H-Indazolo[2,1-B] Phthalazine-Triones Catalyzed by Ionic Iiquid", Advanced Materials Research, Vols. 332-334, pp. 1884-1887, 2011