Suresh T. Gaikwad

Nanosized TiO2 as a Recyclable Heterogeneous Catalyst for the Synthesis of Tetrahydrobenzo[b]pyran Derivatives

Abstract An electrochemical reduction method was used for the preparation of TiO2 nanoparticles in which agglomeration with formation of undesired metal powders is prevented by the presence of ammonium stabilizers. These synthesized nanoparticles were characterized by UV–Visible, XRD, SEM–EDS and TEM analysis techniques. These synthesized nanoparticles of TiO2 were tested as heterogeneous catalyst for the synthesis of tetrahydrobenzo[b]pyran derivative using three components reaction of aromatic aldehyde, dimedione and malononitrile by simply stirring at room temperature in a solvent free condition.

Microwave-Assisted One-Pot Synthesis of Octahydroquinazolinone Derivatives Using Molybdenum Oxide Nanoparticles in Solvent-Free Condition

Molybdenum oxide nanoparticle has been shown to be an inexpensive, efficient and mild catalyst for the one-pot synthesis of octahydroquinazolinone derivatives using dimedone, urea/thiourea and appropriate aromatic aldehydes under microwave-irradiation. Molybdenum oxide nanoparticles were prepared by electrochemical reduction method in which parameters such as current density, solvent polarity, distance between electrodes, and concentration of stabilizers are used to control the size of nanoparticles.Graphical AbstractMolybdenum oxide nanoparticle has been shown to be an inexpensive, efficient and mild catalyst for the one-pot synthesis of octahydroquinazolinone derivatives using dimedone, urea/thiourea and appropriate aromatic aldehydes under microwave-irradiation.

Nanocrystalline titanium dioxide catalyst for the synthesis of azlactones

Abstract Titanium dioxide nanoparticles were prepared by a electrochemical reduction method using parameters such as current density, solvent polarity, distance between electrodes, and concentration of stabilizers to control the size of the nanoparticles. The nanoparticles were characterized by UV-Vis spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy, and their catalytic performance was tested for the synthesis of a series of 4-aryldiene-2-phenyl-5(4)-oxazolones from the cyclodehydration and condensation of the respective aldehyde, hippuric acid and acetic anhydride. Easy availability, reusability and eco-friendliness were some prominent features of the nanocrystalline titanium dioxide catalyst.

Nanosized MoO3 as a reusable heterogeneous catalyst for the synthesis of 2,6-bis(benzylidene)cyclohexanones

Abstract Crystalline MoO3 nanoparticles were obtained by electrochemical synthesis process using tetrapropylammonium bromide as a stabilizer and structure-directing agent in ACN:THF(4:1) solvent. Formation of MoO3 nanoparticles took place at a constant supply current of 14 mA/cm2. These synthesized MoO3 nanoparticles were characterized by UV-Vis spectroscopy, FT-IR spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM). So prepared MoO3 nanoparticles were used as a heterogeneous catalyst for the synthesis of 2,6-bis(benzylidene)cyclohexanone derivatives. This protocol offers several advantages, such as simple work-up procedure, recyclability of the catalyst, excellent product yield in a short reaction time and purification of products with a non-chromatographic method.

Green synthesis of 2-aryl benzothiazole heterogenous catalyzed by MoO3 nanorods

Abstract The synthesis of MoO3 nanoparticles was done by the electrochemical method by using tetra butyl ammonium bromide (TBAB) as a stabilizer and structure directing agent in acetonitrile (ACN):tetrahydrofuran (THF) (4:1) solvent at a constant current supply of 18 mA/cm2. After heating the nanoparticles to 500°C in a muffle furnace, MoO3 nanorods were obtained. These synthesized MoO3 nanorods were characterized by UV-visible spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD) and scanning electron microscopy. The prepared nanorods were used as heterogeneous catalysts for the synthesis of 2-aryl benzothiazole derivatives. This protocol offers several advantages such as a green method, simple work-up procedure, recyclability of the catalyst and excellent product yield in a short reaction time.