V. Arun, K.R. Sankaran, Efficient and Eco-Friendly Synthesis of Fluorenone Azines by Using Sulphated Titania Acid Catalyst, ILCPA Volume 58, International Letters of Chemistry, Physics and Astronomy (Volume 58)
https://www.scipress.com/ILCPA.58.137
Abstract:
    Conjugated unsymmetrical azines have been synthesized in the presence of acid catalyst sulphated-titania (TiO<sub>2</sub>-SO<sub>4</sub><sup>2-</sup>) from fluorenone hydrazone with substituted aldehydes and acetophenones by using mortar and pestle. The scope of present synthetic route avoid in solvents, simple operating method and shorter reaction time. Special feature of synthetic method is recyclable catalyst for all in reactions.
Keywords:
    Reusability Catalyst, Solvent Free, Sulphated Titania, Unsymmetrical Azines