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An efficient approach for the highly diastereoselective construction of functionalized cyclopenta[d][1,2]oxazines via sequential oxyamination and Pauson-Khand reaction of readily accessible propargylic alcohols has been developed. Furthermore, the ring closing metathesis of these N-O linked 1,7-enynes afforded vinylated-[1,2]oxazines in good yields. The reduction of the N-O bond of the obtained cyclopenta[d][1,2]oxazine is accomplished to access cyclopentenone-based amino alcohols.

Iron oxide (FeOx) supported on 1:3 carbon-alumina (ICA) was prepared by wet impregnation method. Oxidized and reduced forms of Fe in ICA catalyst were achieved by diluted H2O2 and hydrazine hydrate treatments, respectively. Three different oxidation states of Fe present in magnetite (Fe2+ and Fe3+), hematite (Fe3+) and wustite (Fe2+) were confirmed by XPS, powder-XRD, H2-TPR, TGA, NH3-TPD and N2-physisorption analysis. Among the synthesized catalysts, in comparison with hematite and wustite phases, magnetite phase offered high catalytic activity in ethylbenzene dehydrogenation reaction. The presence of CO2 in the reaction mixture was found to leave intact the activated carbon support structure.

Despite the enormous interest raised in a few industrially important reactions (ammonia synthesis and decomposition, hydrodenitrogenation, hydrodesulphurization, hydrogenation, dehydrogenation and reforming reactions) molybdenum nitrides are the less studied class of compounds and fascinated keen attention to replace the noble metals as the catalytic activities of these materials resembles or exceed to that of noble metals. Out of the above said reactions nitride catalysts have been extensively studied for ammonia synthesis and decomposition reactions due to the presence of active molybdenum–nitrogen sites. Nitride materials can be produced by incorporation of nitrogen into the interstitial position of the early transition metals by dissimilar methods at higher temperatures. The present review focus mainly on the synthesis of binary and ternary molybdenum nitrides via different routes and application of these materials to the industrial catalytic reactions.

The present work is aimed to produce γ-valerolactone (GVL) from ethyl levulinate hydrogenation over non-noble metal cobalt catalysts at atmospheric pressure in continuous process. Various supported (SBA-15, SiO2, Al2O3, ZrO2, and TiO2) cobalt catalysts were prepared by wet impregnation method and characterized by XRD, N2 physisorption, SEM, TEM, NH3-TPD, H2-TPR and H2-pulse chemisorption techniques. The yield of GVL follows the trend Co/SBA-15 > Co/SiO2 > Co/Al2O3 > Co/ZrO2 > Co/TiO2 similar to trend in active Co metal surface area. The catalytic activity of the supported Co catalyst is strongly influenced by the dispersion and particle size of the Co.

Aiming at synthesizing alkyl levulinates via alcoholysis of furfuryl alcohol in continuous mode for the first time an attempt is made using cheapest and eco-friendly solid acid catalysts. Different silica supported solid acid catalysts containing the oxides of aluminium, tungsten, zirconium and titanium have been prepared. The nature, number and strength of surface acidic sites were evaluated by DRIFT spectroscopy with pyridine adsorption and NH3-TPD and also structural and textural features of the catalysts have been investigated by XRD and BET surface area techniques. Al2O3/SiO2 catalyst exhibited better activity with 100% conversion of furfuryl alcohol and 92.8% selectivity of methyl levulinate, which may be due to more number of surface acidic sites with large number of weak Lewis acidic sites. The catalytic activity of these solid acid catalysts is as follows: Al2O3/SiO2 > ZrO2/SiO2 > WO3/SiO2 > TiO2/SiO2. This is well correlated with the number of surface acidic sites. The stable catalytic activity during the 10 h time-on-stream study confirmed the sturdiness of Al2O3/SiO2 catalyst and also it is active for the selective formation of ethyl, n-propyl, n-butyl levulinates.

With the aim of producing high potential biomass derived chemicals and biofuels in safe environment, carbon–MgO composite (MgO-CX, X = wt% of carbon content) eco-friendly metal-free catalysts have been prepared via in-situ transformation technique using rice grain as carbon precursor. All these MgO-CX catalysts are characterized by X-ray diffraction, BET surface area, temperature programmed desorption of CO2, Raman and FT-IR. The MgO-CX catalysts are subjected to catalytic transfer hydrogenation of furfural into furfuryl alcohol, using isopropanol as H-donor in continuous process at atmospheric pressure. MgO-C68 is the best catalyst of this series, which exhibited 100% conversion of furfural with 98% selectivity of furfuryl alcohol. The existence of large number of suitable basic sites on the surface of MgO-C68 catalyst is responsible for its superior catalytic activity and durability.

The present work highlights the application of solid acid catalyst to produce alkyl levulinate from levulinic acid in continuous mode under vapor phase conditions. In this context, tungsten oxide incorporated SBA-16 catalysts were prepared by one pot direct synthesis method and evaluated for the titled reaction. Under optimized reaction conditions, 3 wt% WO 3 -SBA-16 catalyst delivered complete conversion of levulinic acid with 95% selectivity towards ethyl levulinate. The synthesized catalysts were characterized to know the physico-chemical features by various techniques, namely, X-ray diffraction, N 2 physisorption, temperature programmed reduction of hydrogen (H 2 -TPR), temperature programmed desorption of ammonia (NH 3 -TPD), DR-UV–vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The characterization results suggest that, the superior catalytic activity can be ascribed due to the enhanced acidity of SBA-16 obtained through incorporation of tungsten oxide and easy of accessibility for the dispersed active sites through uniform pore channels. The constant catalytic activity in 10 h time on study shows the sturdiness of the catalyst and the spent catalyst can be regenerated several times. Moreover, various alkyl levulinates (methyl, n -propyl, and n -butyl) were synthesized with more than 90% selectivity over this catalyst.

With an aim to set up acid-base functionalities in mesoporous SBA-15, herein we report one pot hydrothermal synthetic strategy to incorporate LaPO4 into SBA-15 (LaP-SBA-15). ICP-OES and EDX results confirmed successful incorporation of large amount of LaPO4 in SBA-15. The small angle XRD, N2-isotherms and TEM studies unveiled the presence of ordered mesoporous and its characteristic features in LaP-SBA-15 catalysts. The incorporated LaPO4 is existed in monoclinic phase which is authenticated by wide angle XRD and FT-IR results. In addition to this, electron microscope images of LaP-SBA-15 catalysts clearly illustrate the crystalline growth of monoclinic LaPO4 nanoparticles across the hexagonal mesopore channels of SBA-15. NH3/CO2 -TPD demonstrated existence of both surface acidic and basic sites which are imparted to SBA-15 through LaPO4 incorporation. LaP-SBA-15 catalysts have been evaluated for the selective O-alkylation of phenol with methanol in continuous process. LaP-SBA-15 catalysts offer excellent catalytic activity and selectivity towards anisole. The surface acidic and basic sites could be tuned by adjusting the LaPO4 content, which leads to the tunable selectivity in the O-methylation of phenol. Especially, 30 wt % LaP-SBA- 15 catalyst exhibited constant selectivity to anisole up to 16 h of time-on-stream. This superior catalytic performance of 30 wt% LaP-SBA-15 catalyst is attributed to dispersion of balanced amount weak acidic and moderate basic sites through mesopores and the transportation of reactant and product molecules through uniform channels of SBA-15 containing LaPO4.