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Three-dimensional mesoporous aluminosilicate catalysts (AlKIT-5) with cage type porous structure were prepared using Pluronic F127 as a structure-directing agent in a highly acidic medium. The catalysts were characterized by XRD, N2 adsorption, and TPD of NH3. The acidity and the acid strength of the AlKIT-5 were controlled by varying the amount of Al in the silica framework of the mesochannels. Further, the catalysts were utilized for a facile nucleophilic ring opening of epoxides with various aromatic and aliphatic amines under mild reaction condition. The reactions were found to be highly selective and efficient, affording the corresponding β-aminoalcohols in good yield. It was found that the catalyst is recyclable and the activity of the catalyst was not diminished even after several reaction cycles. Refereed/Peer-reviewed

Here we demonstrate the preparation of highly ordered two-dimensional P6mm mesoporous niobium silicates with unprecedented loadings of niobium in the silica framework (up to nSi/nNb ratio of 6.1) and highly winding morphologies maintaining regularly aligned arrays of nanochannels through a simple adjustment of the molar water to hydrochloric acid ratio (nH2O/nHCl) in the synthesis gel using nonionic surfactant as a template in a highly acidic medium. X-ray diffraction (XRD), N2 adsorption, high-resolution scanning electron microscopy (HRSEM), energy-dispersive spectrometry (EDS), and high-resolution transmission electron microscopy (HRTEM) results provided strong evidence of the presence of highly ordered two-dimensional structure in the NbSBA-15 materials with a very high content of niobium and winding morphologies, whereas UV-visible diffuse reflectance spectroscopy (UV-vis DRS) confirmed the presence of tetrahedrally coordinated niobium in the silica framework. Moreover, the loading of Nb in the silica framework can be controlled by a simple adjustment of the n H2O/nHCl and the amount of Nb source in the synthesis gel. Thus, a hitherto unachieved loading of niobium in the silica framework with a controlled manner, considered by many researchers to be impossible to achieve for the highly ordered mesoporous SBA-15 materials because of the highly acidic synthesis condition and the framework connectivity constraints, has been reported. We also found that the Nb incorporation could be a way to control the morphlogy of the NbSBA-15 materials. The morphology of the materials changed from rod to semispherical to "winding road" shape with decreasing the nSi/nNb from 22.5 to 6.1. Moreover, the detailed mechanism on the morphological control as a function of Nb content has also been proposed. This simple one-step technique to control the morphology, which would be of general interest for the application requiring the materials with different morphology, and Nb loading in a highly acidic medium synthesis have not been reported so far. Refereed/Peer-reviewed

Acetal and acylal formation reactions of organic compounds are efficiently catalyzed by zirconia-supported mixed oxide systems under liquid-phase reaction conditions. 15WZ-750 (where, W = WO3 and Z = ZrO2) was the most active catalyst, which could be recyclable without loss in its activities. This study reports the use of a non zeolitic solid acid catalyst systems based on zirconia-supported isopoly and heteropoly acids, which are highly efficient, chemoselective, eco-friendly and cost effective catalysts for use in the condensation reactions. Refereed/Peer-reviewed