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The article reports on the alteration of an iridium complex's form in the absence or presence of hydrogen. Iridium complex catalyzes the heterocyclic organic compounds' dehydrogenation, and in the presence of hydrogen alters itself to catalyse the contrary reaction. Iridium complex alters back to do dehydrogenation again, and the procedure is repeated. it appears trivial for a catalyst to be able to catalyze both the forward and contrary reactions because of the principle of microscopic reversibility.

Substrate (II) is selected as the best educt for the title reaction. Aromatic thiols add to the double bond to form sulfurated products which contain carbonyl groups at the α and β positions in relation to the stereogenic center. The ∧ configuration at the iridium center of the catalyst (I) leads to an (S) configuration of the target thioethers which are of interest as synthons for chiral sulfur-containing pharmaceuticals. [ABSTRACT FROM AUTHOR]

The article reports the first protocol for regioselective functionalization of aromatic C-H bonds using acid chlorides as the coupling partners via C-H bond activation by rhodium catalysis under phosphine-free conditions. According to the authors, efficient regioselective functionalization of aromatic C-H bonds has been realized by Rh(I) catalysis using acid chlorides as coupling partners.

Abstract: A modified synthesis of tellurophene by reaction of diacetylene with sodium telluride is described. The primary modification involves the convenient in situ generation of sodium telluride by reduction of tellurium metal with NaBH4 in water. [Copyright &y& Elsevier]

The article focuses on the study about the rhodium-catalyzed asymmetric rearrangement of alkynyl alkenyl carbinols, particularly its synthetic equivalent to asymmetric conjugate alkynylation of enones. The researchers found a new method of introducing alkynyl groups to the beta-position of alpha,beta-unsaturated ketones with high enantioselectivity, which was realized by rhodium-catalyzed asymmetric1,3-migration of alkynyl groups from 1 position to 3 in alkynyl alkenyl carbinols.

The article focuses on the isolation of the resting state of the iridium catalyst and the asymmetric allylic substitutions catalyzed by iridium. It shows that the active catalyst contains the cyclometalated core of the complex generated in situ by reaction of alkylamines and the phosphoramidite ligand. The experiment also indicates that reaction of the iridium species with the allylic esters in reversible.

A new atom economical approach for the preparation of 1,2,3,4-tetrahydroquinolines can be achieved by means of the intramolecular hydroaminomethylation of 2-isopropenylanilines, mediated by an ionic diamino rhodium catalyst that does not require phosphine—this reaction is highly chemo- and regioselective, and it occurs in good isolated yields. [ABSTRACT FROM AUTHOR]

The article focuses on reactions of intramolecular C-H amination with reference to rhodium (II)-catalyzed decomposition of azidoacrylates. It has been stated that the activation of C-H bonds through dirhodium (II) carbenoids and nitrenoids permits access to valuable carbocycles and heterocycles. It is estimated that the electronic nature of the rhodium catalyst ligands determines its activities.

The article offers a market review of platinum in South Africa. Production of all platinum group minerals rose strongly as companies invested in expansion. Global demand for platinum rose by 1.2% to 6.78 million ounces in 2006, supported by an increase in the use of platinum for autocatalysts and a range of industrial applications. Production of platinum in South Mines promoted Africa at Everest and Two Rivers and a strong performance from Anglo Platinum.

The article presents abstracts of research relating to organometallic chemistry. It includes "Homogenous, Assymetric Reductions of Heterocycles," "Decarboxylative Syntheses of Biaryls" and "Bisoxazolines Holding Hands."

The article offers information about a study conduted to explore the generation of a series of rhodium alkoxo complexes with olefin coligands that generate products from C--O bond formation. The study prepared a series of bis-(phosphine) rhodium (I) alkoxides containing an accompanying olefin ligand. Furthermore, results of the study records intramolecularity, lack of evidence for ionic intermediates, and syn stereochemistry of the cyclizations as characteristics of a migratory insertion mechanism.

Selective ring hydrogenation of naphthols to tetrahydronaphthols and tetralones proceeded at 323 K over a charcoal supported rhodium catalyst in supercritical carbon dioxide. [ABSTRACT FROM AUTHOR]

The hydroformylation of 1-dodecene under aqueous/organic two-phase reaction conditions with rhodium catalysts derived from BISBIS (sodium salt of sulfonated 2,2′-bis (diphenylphosphinomethyl)-1,1′-biphenyl) in the presence of cationic surfactants was studied; regioselectivities appear to be sensitive to pressure. In all cases, the activities and regioselectivities for linear aldehyde were higher. [ABSTRACT FROM AUTHOR]

The title reaction offers an efficient and clean method to synthesize pyridoisoindoles in moderate to excellent yields in the presence of Cu salts. [ABSTRACT FROM AUTHOR]

A novel iridium catalyst is prepared and tested in the enantioselective hydrogenation of 1,1-diarylalkenes (I) and (III) bearing a meta-directing group. [ABSTRACT FROM AUTHOR]

The South African minister of science and technology, Naledi Pandor, wants the country to capture 25% of the global market for the production of novel platinum group metal (PGM) catalysts for hydrogen and fuel cell applications. With platinum a key component for most fuel cells, Pandor believes the country is well placed to achieve this, since it has three-quarters of the world''s known platinum reserves. [Copyright &y& Elsevier]

The article discusses the interception of catalytic olefin and alkyne hydrogenations through potentially nucleophilic organometallic intermediates. The carbon-carbon bond formation is appealing from an efficiency standpoint because it eliminates the need to prepare the organometallic nucleophiles stoichiometrically. Meanwhile, a researcher show that an iridium catalyst effectively couples alkyl-substituted alkyns to imine electrophiles during hydrogenation to yield allylic amine products. The reaction would lead to high selectivity for the E olefin isomer.

cis-4-tert-Butylcyclohexanol was obtained with a high cis ratio (cis/(cis + trans) = 0.9) in the hydrogenation of 4-tert-butylphenol over a carbon-supported rhodium catalyst along with hydrochloric acid in supercritical carbon dioxide solvent. [ABSTRACT FROM AUTHOR]

The activity of Ir catalysts for selective catalytic reduction of nitrogen monoxide by carbon monoxide was drastically enhanced by combining iridium and tungsten oxide on a silica support. [ABSTRACT FROM AUTHOR]