The reduction of nitro compounds to the corresponding amines is one of the most utilized catalytic processes in the fine and bulk chemical industry. The latest development of catalysts with cheap metals like Fe, Co, Ni and Cu has led to their tremendous achievements over the last years prompting to their greater application as "standard" catalysts. In this review we will comprehensively discuss the use of homogeneous and heterogeneous catalysts based on non-noble 3d-metals for the reduction of nitro compounds using various reductants. The different systems will be revised considering both the catalytic performances and synthetic aspects highlighting also their advantages and disadvantages.

Improved molecularly-defined cobalt catalysts for the hydrogenation of carbon dioxide to methanol have been developed. A key factor for increased productivity (up to twofold compared to previous state-of-the-art-system) is the specific nature of substituents on the triphos ligand. In addition, the effect of metal precursors, and variations of additives have been investigated.

An active and renewable catalyst for olefin hydrogenation was obtained by inclusion of cobalt in a carbon matrix derived from the pyrolysis of chitosan.

Hydroformylation of olefinsh as been studied in the presence of specific heterogeneous cobalt nanoparticles. The catalytic materials were preparedb yp yrolysis of preformed cobalt complexes deposited ontod ifferent inorganic supports. Atomic absorption spectroscopy (AAS) measurements indicated ac orrelation of catalysta ctivity and cobalt leachinga sw ell as as trong influence of the heterogeneous support on the productivity.T hese new,l ow-cost, easy-tohandle catalystsc an substitute more toxic, unstablea nd volatile cobalt carbonylc omplexes for hydroformylations on a laboratory scale.

An overview of the synthesis and chemistry of acylborane compounds is presented. Acylboranes are a rare class of boron compounds, previously proposed as intermediates in several transformations and considered to be difficult to prepare. Methodologies for the preparation of acylborane compounds are based on both electrophilic and nucleophilic sources of boron. The former methods include addition of electrophilic boron reagents to acyl-anion equivalents, while the latter methods are based on boryl anion reagents which are trapped by electrophiles, such as aldehydes, diethyl carbonate and ethyl acetate. New methods to achieve acylboron-compounds based on oxidation of MIDA α-hydroxyboronates or α-bromomethyl alcohol are discussed. A one-step catalytic C-B coupling reaction for preparing acylboranes from palladium-catalyzed borylation of acyl chlorides using nucleophilic borylzinc reagents is included. Applications of acylboranes in chemoselective amide-bond forming reactions, converting them into functionalised boron derivatives are also discussed.

Homogeneously cobalt-catalyzed hydrogenation of cyclic and acyclic carbonates: beneficial effects of 2,2,2-trifluoroethanol and triphos-derivatives.

Biomolecule modified supported cobalt nanoparticles efficiently hydrogenate diverse natural, industrial and functionalized olefins in water under mild conditions.

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