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Glycerol acetylation and esterification reactions with acetic anhydride and acetic acid respectively give acetins, in which di and tri acetins are commercially important products used as fuel additives.

Octahedral MnO 2 molecular sieve (OMS) was prepared using hydrothermal synthesis route in the absence and in the presence of urea. OMS was also prepared by solvent free method.Catalysts were characterized by the complementary combination of X-ray diffraction, N 2adsorption, scanning electron microscope, UV-visible spectroscopy, thermo gravimetric analysis, and NH 3 & CO 2 temperature programmed desorption techniques. Catalysts were investigated in the oxidation of benzyl alcohols, hydration of aromatic/heterocyclic nitrile and condensation reactions (Knoevenagel and Aldol). Furthermore, applicability of the catalyst was extended in one-pot tandem conversion of benzyl alcohol to 2-benzylidenemalononitrile, (E)-chalcone, and 2,3-dihydro-1,5-benzothiazepine. 2-Benzylidenemalononitrile and (E)-chalcone were prepared by two steps tandem reactions from benzyl alcohol, whereas 2,3-dihydro-1,5-benzothiazepine was prepared by three steps tandem reaction from benzyl alcohol. Recycling study show that no significant decrease in the catalytic activity was observed even after five recycles. To the best of our knowledge, this is the first report, which shows that OMS materials obtained using different synthesis methods exhibited significant difference in the catalytic activity in the above mentioned reactions. flask fitted with a condenser. Product was filtered, washed with deionised water, and dried at 120 C for 8-10 h. Material is designated as OMS-2 (Yield = 80%). Synthesis of OMS-2 by solvent free methodOMS-2 was prepared under solvent free condition by following the reported procedure. 33 In a typical synthesis, 2.37 g KMnO 4 (0.06 mol) and 5.51 g (0.09 mol) of Mn(Ac) 2 .4H 2 O were mixed and grounded in a mortar. The mixed powder was kept in a Teflon lined autoclave at 120C for 12 h. The resulting black product was thoroughly washed with deionised water to remove any ions which may remain in the product, and dried at 120C for 8-10 h. Material is designated as OMS-2-SF (Yield = 56 %). Hydrothermal synthesis of OMS-2 using urea 8 mmol of KMnO 4 (1.26 g) was dissolved in 20 mL of deionised water. 28 mmol urea (1.68 g) was added (in 15 minutes) to the solution and the reaction mixture was stirred for 30 minutes at ambient condition. After 30 min, resulting solution was added drop wise to a vigorously stirred mixture of MnSO 4 .H 2 O (10.5 mmol, 1.77 g in 6 mL water) and conc. HNO 3 (0.6 mL). The reaction mixture was refluxed for 24 h in a round bottom glass flask fitted with a condenser. Product was filtered, washed with deionised water, and dried at 120C for 8-10 h. OMS-2 material prepared with urea is designated as OMS-2-U (Yield = 99 %). Catalyst characterizations X-ray diffraction (XRD) patterns were recorded in the 2θ range of 5-80° with a scan speed of 2°/min on a PANalytical X'PERT PRO diffractometer using Cu Kα radiation (λ=0.1542 nm, 40 kV, 40 mA) and a proportional counter detector. Nitrogen adsorption measurements were performed at -200C by Quantachrome Instruments, Autosorb-IQ volumetric adsorption analyzer....

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A sulfonic acid-functionalized mesoporous polymer (MP-SO3H) catalyst was prepared via post-synthetic modification of mesoporous polydivinylbenzene.

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Mesoporous polymers (MP) were synthesized by free radical polymerization of divinylbenzene by a solvothermal method followed by sulfonic acid functionalization by a post synthetic modification with conc.

The generation of Brønsted (Sn–OH) and Lewis (coordinatively unsaturated metal centers) acidic sites on the solid surface is a prime demand for catalytic applications. Mesoporous materials are widely employed as catalysts and supports owing to their different nature of acidic sites. Nevertheless, the procedure adopted to generate acid functionalities in these materials involves tedious steps. Herein, we report the tunable acidic sites containing Brønsted sites with relatively varied acid strength in tin oxide by employing soft template followed by simple thermal treatment at various temperatures. The readily accessible active sites, specifically Brønsted acidic sites distributed throughout the tin oxide framework as well as mesoporosity endow them to perform with exceptionally high efficiency for epoxide ring opening reactions with excellent reusability. These features promoted them to surpass stannosilicate catalysts for the epoxide ring opening reactions with alcohol as a nucleophile and the study was extended to aminolysis of epoxide with the amine. The existence of relatively greater acid strength and numbers in T-SnO2-350 catalyst boosts to produce a high amount of desired products over other tin oxide catalysts. The active sites responsible in mesoporous tin oxide for epoxide alcoholysis were studied by poisoning the Brønsted acidic sites in the catalyst using 2,6-lutidine as a probe molecule.