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The selective hydrogenation of benzofurans in the presence of a heterogeneous non‐noble metal catalyst is reported. The developed optimal catalytic material consists of cobalt‐cobalt oxide core–shell nanoparticles supported on silica, which has been prepared by the immobilization and pyrolysis of cobalt‐DABCO‐citric acid complex on silica under argon at 800 °C. This novel catalyst allows for the selective hydrogenation of simple and functionalized benzofurans to 2,3‐dihydrobenzofurans as well as related heterocycles. The versatility of the reported protocol is showcased by the reduction of selected drugs and deuteration of heterocycles. Further, the stability, recycling, and reusability of the Co‐nanocatalyst are demonstrated. [ABSTRACT FROM AUTHOR]

Catalytic hydrogenation of olefins using noble metal catalysts or pyrophoric RANEY® nickel is of high importance in the chemical industry. From the point of view of green and sustainable chemistry, design and development of Earth-abundant, less toxic, and more environmentally friendly catalysts are highly desirable. Herein, we report the convenient preparation of active cobalt catalysts and their application in hydrogenations of a wide range of terminal and internal carbon–carbon double bonds in water under mild conditions. Catalysts are prepared on multi-gram scale by pyrolysis of cobalt acetate and uracil, guanine, adenine or L -tryptophan. The most active material Co-Ura/C-600 showed good productivity in industrially relevant hydrogenation of diisobutene to isooctane and in natural oil hardening. [ABSTRACT FROM AUTHOR]

Hydroformylation of olefins has been studied in the presence of specific heterogeneous cobalt nanoparticles. The catalytic materials were prepared by pyrolysis of preformed cobalt complexes deposited onto different inorganic supports. Atomic absorption spectroscopy (AAS) measurements indicated a correlation of catalyst activity and cobalt leaching as well as a strong influence of the heterogeneous support on the productivity. These new, low‐cost, easy‐to‐handle catalysts can substitute more toxic, unstable and volatile cobalt carbonyl complexes for hydroformylations on a laboratory scale. Co catalysis: A new class of low‐cost, easy‐to‐handle materials for lab‐scale hydroformylation is reported. The pyrolysis of preformed Co complexes deposited onto inorganic supports resulted in immobilised cobalt nanoparticles for oxo synthesis. The most active materials Co/phen@TiO2 and Co/phen@C represent convenient reservoirs for active homogeneous cobalt species, and thus can substitute the common, but toxic, dicobaltoctacarbonyl complex. [ABSTRACT FROM AUTHOR]