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α-Alkylation reactions between amides and alcohols, with dimethylacetamide-stabilized Ru nanoparticles (NPs) as the catalyst, were investigated. The reactions proceeded with low catalyst loadings compared to metal complexes. Characterizations of the Ru NPs were performed by X-ray photoelectron spectroscopy, X-ray absorption fine structure spectroscopy, and various techniques. Control experiments revealed the reaction mechanisms, which proceeded via hydrogen autotransfer with alcohols.

This paper reports novel Cu-catalyzed three-component coupling reactions using nitriles, 1,3-dienes and silylboranes. The desired reactions proceed at room temperature and yield β,γ-unsaturated ketones with a (dimethylphenylsilyl)methyl moiety at the α-position. Diverse nitriles participate in the reaction and the corresponding products were obtained in good to high yields with high regioselectivity.

A bulky carboxylic acid bearing one 1-adamantylmethyl and two methyl substituents at the α-position is demonstrated to work as an efficient carboxylate ligand source in Pd-catalyzed intermolecular C(sp 2 )-H bond arylation reactions. The reactions proceeded smoothly under mild conditions, taking advantage of the steric bulk of the carboxylate ligands.

π-Conjugated porphyrin-containing hollow structures with defined axis-length were successfully synthesized by a two-step template method, i.e., template-assisted cyclization and oligomerization. During the oligomerization, templates played important roles in controlling the reaction rates and the axis lengths. The hollow structures exhibited an extended effective π-conjugation because of the high coplanarity between porphyrins.

We describe herein the synthesis of a Ni(ii) bis(dithiobenzoate)-type complex three-dimensionally insulated by a [1]rotaxane structure to reveal the importance of the insulation. Under cyclic voltammetry conditions, the complex showed a stable and reversible redox behavior in contrast to a non-insulated reference complex, clearly demonstrating the effectiveness of the rotaxane-type insulation as a new method of kinetic metal complex stabilization.

The hydroallylation of allenes was developed by employing a hydrosilane and allyl chlorides in the presence of a copper catalyst. The reaction provided (E)-1,5-dienes mainly in good to high yields.

N-Heterocyclic carbenes bearing poly(ethylene glycol) chains of different lengths have been designed and employed as ligands in palladium-catalyzed coupling reactions. The catalyst system having longer chains was found to be highly efficient for Suzuki-Miyaura coupling and borylation reactions employing aryl chlorides under mild reaction conditions.

A highly selective carbon-carbon bond-forming transformation of carbon dioxide (CO2) to alcohol oxidation level has been disclosed. By employing a copper/bisphosphine catalyst system and hydrosilanes as mild and easy-to-handle reducing agents, various allenes can be reacted with CO2 to regioselectively obtain homoallylic alcohols. Esters and other reducible functionalities on the allenes remain intact during the reaction, whereas CO2 is reduced to alcohol oxidation level.

The cobalt-catalyzed carboxylation of propargyl acetates with CO2 (1 atm) is described. The reaction proceeds at room temperature in the presence of Mn powder as a reducing reagent. Various propargyl acetates are converted to the corresponding carboxylic acids in good to high yields.

Palladium-catalyzed formal arylacylation of allenes using acid chlorides and arylboronic acids has been achieved. The reaction afforded the corresponding α,β-unsaturated ketones regio- and stereoselectively.

A new method for the synthesis of an insulated π-conjugated monomer was developed via the sequential self-inclusion followed by the elongation of the π-conjugated unit. The monomer was utilized in the synthesis of stimuli-responsive insulated molecular wires.

Recent carbon-carbon bond forming reactions of carbon dioxide with alkenes, alkynes, dienes, aryl zinc compounds, aryl boronic esters, aryl halides, and arenes having acidic C-H bonds are reviewed in which transition-metal catalysts play an important role.

Aryl formates are efficient carbon monoxide sources in palladium-catalyzed esterification of aryl halides. The carbonylation readily proceeds at ambient pressure without the use of external carbon monoxide to afford the corresponding esters in high yields.

We developed a new method for the synthesis of an organic-soluble insulated molecular wire (IMW) with permethylated cyclodextrin (PMCD); this method involves click polymerization of linked [2]rotaxane containing azide and alkynyl groups at both ends of a π-conjugated guest., (This journal is © The Royal Society of Chemistry 2012)

Ruthenium-based metathesis catalysts with a N-heterocyclic carbene ligand bearing 2,3,4,5-tetraphenylphenyl moieties (1-TPPh and 1-TPPh*) are developed. The highly active catalyst system has been realized in THF by the combination of 1-TPPh* and CuCl as a phosphine scavenger., (This journal is © The Royal Society of Chemistry 2011)

We developed a new method for synthesizing an organic-soluble insulated molecular wire (IMW) using permethylated cyclodextrin (PMCD). The IMW obtained using this method is highly soluble in a variety of organic solvents and has a high covering ratio, regioregularity, rigidity, photoluminescence efficiency, and interchain hole mobility., (This journal is © The Royal Society of Chemistry 2011)

The catalytic decarbonylation of aldehydes has been developed using commercially available [IrCl(cod)](2) and PPh(3) under mild conditions, and the method could be widely applicable to various substrates with different functionalities.

Novel rhodium(I) complexes with N-heterocyclic carbenes bearing a 2,3,4,5-tetraphenylphenyl and its higher dendritic frameworks were synthesized and the complexes were used as catalysts in rhodium-catalyzed hydrosilylation of alpha,beta-unsaturated ketones to show high 1,4-adduct selectivity.

Novel dendrimer N-heterocyclic carbene complexes with rhodium(I) located at the core were synthesized, and a positive dendrimer effect was found in the hydrosilylation of ketones catalyzed by them.