Herein, we report solvothermal carbonization of biomass, such as glucose, in the presence of a small amount of graphene oxide (GO) as a structure-directing agent that yields a carbon-based graphene oxide monolith (CGO monolith). The CGO monolith was functionalized with chlorosulfonic acid under mild reaction conditions to achieve sulfated carbon-based graphene oxide (SO3H@CGO monolith). It was used for the esterification of levulinic acid with benzyl alcohol and the etherification of benzyl alcohol with butanol as model reactions. The activity of the catalyst was compared with different solid acid catalysts, such as GO, CGO monolith, nanocrystalline sulfated titania (NCST), SO3H@HTC (sulfated hydrothermal carbon), amberlyst-15, and SO3H@GO for esterification of levulinic acid with benzyl alcohol. The SO3H@CGO monolith showed excellent conversion (97%) toward benzyl levulinate at 110 °C with low catalyst loading (0.008 g/cm3) and mole ratio. The catalyst was well characterized by SEM, EDXA, TEM, XRD, FTIR, BET surface area, CHNS, and TGA analysis. The role of various parameters, such as speed of agitation, molar ratio, catalyst loading, and temperature, on the reaction rate using SO3H@CGO monolith as catalyst was studied to establish the mechanism of the reaction, and the catalyst was reused up to five times, including the fresh one. The overall process is novel and green.

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Synthesis of palladium nanoparticles supported on carbon based graphene oxide monolith (Pd@CGO monolith) is reported here. It was prepared by solvothermal carbonization of glucose with small amount of graphene oxide (GO) as structure directing agent. It provides large and flat surface for anchoring Pd nanoparticles. CGO monolith impedes Pd particles migration and increases interaction between Pd nanoparticles and support, which leads to enhanced activity. It was used in Sonogashira coupling and hydrogenation of alkenes and nitrobenzene. The activity of Pd@CGO monolith was compared with 5 % Pd@GO and 5 % Pd/C for Sonogashira coupling of phenyl-acetylene with iodobenzene. Pd@CGO monolith showed excellent conversion (93 %) at 90 8C with low catalyst loading (1 3 10 À3 g/cm 3 ) under ligand and copper free reaction conditions. Pd@CGO monolith was well characterized by different analytical techniques. The effect of solvent, base, speed of agitation, mole ratio, catalyst loading and temperature was studied using Pd@CGO monolith. Also, a reaction mechanism was proposed and kinetic model developed. The catalyst was recycled up to four times with no loss of activity. It was highly stable showing no Pd leaching.[a] Dr.

Spinel ferrite magnetic nanoparticles are superior to the conventional catalysts. Here we report the synthesis of different types of spinel ferrite nanoparticles, MFe 2 O 4 (M = Cu, Mn, Mg, Co, Ni), by a hydrothermal method. The prepared spinel ferrite nanoparticles were used for the N-arylation reaction of indole with iodobenzene. Among these CuFe 2 O 4 nanoparticles exhibited the best activity and selectivity for N-arylation under ligand free condition. The prepared spinel ferrite microspheres were well characterised by using various characterization techniques such as TEM, XRD, XPS, SEM, EDXA, FT-IR, N 2 adsorption desorption measurements and TGA. The effect of various parameters were studied such as solvent, base, speed of agitation, mole ratio, catalyst loading and temperature in the reaction of indole with iodobenzene. Best conversion and yield were achieved at 110 8C and 1 3 10 -3 g/cm 3 catalyst loading. Notably, CuFe 2 O 4 magnetic nanoparticles were completely recovered and could be reused six times without any noticeable loss of activity. Reaction mechanism and kinetics are also presented.[a] Dr.

In this paper, we report copper ferrite supported reduced graphene oxide (CuFe2O4@rGO) synthesis by solvothermal process. The prepared CuFe2O4@rGO catalyst was used for C‐O and C‐N cross coupling reactions. The activity of the catalyst was compared with commercial Cu2O, CuOand CuFe2O4 for C‐O cross coupling of iodobenzene with phenol. CuFe2O4@rGO was the best catalyst with 97% conversion towards iodobenzene at 100°C under ligand free condition which is otherwise normally used. The virgin and five times reused CuFe2O4@rGO catalyst was characterized by XRD, SEM, FTIR, TEM, N2‐adsorption desorption isotherm, XPS and TGA analysis. The effect of solvent, nature of base, speed of agitation, mole ratio, catalyst loading and temperature was studied for phenol and iodobenzene reaction and its activity was further explored in N‐arylation of indole with idobenzene. The best conversion and yield were achieved at 100 °C at 1×10‐3 g/cm3 catalyst loading. Notably, CuFe2O4@rGO was reusable without any loss of catalytic activity for five recycles. Reaction mechanism and kinetics are also presented. The overall process is novel and green.