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A versatile heterogeneous photocatalysis protocol was developed by using ruthenium bipyridyl tethered porous organosilica (Ru-POS). The versatility of the Ru-POS catalyst in organo-photocatalysis was explored by (i) oxidative aromatization of Hantzsch ester, (ii) reductive dehalogenation of alkyl halides, and (iii) functional group interconversion (FGI) of alcohols to alkyl halides. [ABSTRACT FROM AUTHOR]

Highlights: [•] Palladium nanoparticles grafted at the surface of Co-MOF. [•] High catalytic activity in Suzuki and Sonogashira C–C coupling reactions in water. [•] Various aryl halides can be coupled with phenylboronic acid. [•] Coupling between terminal alkynes and aryl halides proceeded without Cu co-catalyst. [•] The catalyst can be reused several times without a noticeable change in activity. [ABSTRACT FROM AUTHOR]

A new highly ordered mesoporous tungstic acid functionalized SBA-15, TAFMC-1 has been synthesized via post-synthesis modification of mesoporous SBA-15 with (3-chloropropyl) triethoxysilane followed by substitution reaction of chlorine atom of the 3-chloropropyl group by tungstic acid group under refluxing conditions in n-hexane. The tungstic acid functionalized mesoporous silica material has been characterized by using small angle powder X-ray diffraction, N2 sorption, HR-TEM, FE-SEM, FT-IR and solid state MAS NMR studies. TAFMC-1 catalyzes the facile one-pot catalytic three-component condensation reaction of resorcinol, aromatic aldehyde and malononitrile for the synthesis of a diverse range of 2-amino-4H-chromenes in aqueous medium. This heterogeneous catalyst can be recycled very efficiently for six consecutive reaction cycles without significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]

Highly efficient and recyclable heterogeneous organocatalysts containing acidic functional groups such as 一CO2H and 一SO3H have been synthesized by post-synthesis modification of 2D-hexagonal mesoporous silica materials SBA-15 and MCM-41, respectively. The CO2H functionalized material is obtained via Schiff-base condensation of 3-aminopropyl grafted SBA-15 with 4-formylbenzoic acid, whereas 一SO3H functionalized material is prepared via partial oxidation of 3-mercaptopropyl grafted MCM-41 with dilute aqueous H2O2. These functionalized mesoporous materials have been thoroughly characterized by powder X-ray diffraction (PXRD), nitrogen adsorption/desorption studies, transmission electron microscopy (TEM) and UV visible diffuse reflectance spectroscopy. Both these materials have highly ordered 2D-hexagonal mesoporous structures with high surface areas and well-defined pore sizes. These acid functionalized materials have been used as heterogeneous catalysts for the condensation of aromatic aldehydes with 2-napthol under mild conditions in the presence or absence of a solvent affording high yields of the value added xanthenes. [ABSTRACT FROM AUTHOR]

For the first time, we have used activated alumina balls (3–5 mm diameter) for amide synthesis from carboxylic acids (unactivated) and amines (unactivated) under neat reaction conditions that produce no toxic by-products and has the advantages of being low-cost, easily available, heterogeneous, reusable and environmentally benign with no troublesome/hazardous disposal of the catalyst. [ABSTRACT FROM AUTHOR]