2004 Condensation reactions

Condensation reactionsO 0120 Hydrotalcite Catalysis in Ionic Liquid Medium: A Recyclable Reaction System for

Heterogeneous Knoevenagel and Nitroaldol Condensation. — Knoevenagel con-densations of various aldehydes and ketones with malononitrile or ethyl cyanoacetate are performed in recyclable systems. Ionic liquids without any catalyst or with a Mg—Al hydrotalcite catalyst, which can be recycled several times without significant loss of activity are used. Hydrotalcites are also efficient catalysts for nitroaldol reac-tions in ionic liquids. — (KHAN*, F. A.; DASH, J.; SATAPATHY, R.; UPADHYAY, S. K.; Tetrahedron Lett. 45 (2004) 15, 3055-3058; Dep. Chem., Indian Inst. Technol., Kanpur 208 016, India; Eng.) — Roy

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