Aqueous-phase hydroformylation of 1-octene: styrene latices as phase-transfer agents

An elegant method for the aqueous-phase hydroformylation of 1-octene with a water-soluble Rh catalyst and amphiphilic latex particles as phase-transfer agents has been developed (see scheme). In this way, substantial concentrations of the olefin in the aqueous catalyst-containing phase were reached, and thus reasonable turnover frequencies under mild reaction conditions could be achieved

Rh(I) coordination chemistry of hexacationic Dendriphos ligands and their application in hydroformylation catalysis

The coordination chemistry of hexacationic Dendriphos ligands L* with respect to Rh(I), as well as their application in Rh-catalyzed hydroformylation reactions, is described. Complexes of the type RhCl(CO)(L*)2 were synthesized and characterized. The results show that Dendriphos ligands are weaker r-donors and/or stronger p-acceptors compared to PPh3. The reaction of L* with [Rh(cod)2]BF4 in MeCN afforded monophosphine-Rh(I) complexes of the type Rh(cod)(MeCN)(L*), which points to the tendency of these ligands to form coordinatively unsaturated metal complexes. The catalytic performance of Dendriphos ligands in the Rh-catalyzed hydroformylation appeared to be dominated by steric effects arising from the large dendritic shells of these ligands. Furthermore, the possibility of tuning the catalytic activity and selectivity of the catalytic species, by changing the six counteranions of the hexacationic Dendriphos ligand, has been investigated. Changing the anions from BF4 to the chiral anions camphorsulphonate or D-Trisphat did not render the hydroformylation reaction of styrene enantioselective, albeit small changes in its regioselectivity were observed

Cellular phones, cordless phones, and the risks of glioma and meningioma (Interphone Study Group, Germany)

Schuz J, Bohler E, Berg-Beckhoff G, et al. Cellular phones, cordless phones, and the risks of glioma and meningioma (Interphone Study Group, Germany). AMERICAN JOURNAL OF EPIDEMIOLOGY. 2006;163(6):512-520

Environmental risk factors for sporadic acoustic neuroma (Interphone Study Group, Germany)

Schlehofer B, Schlaefer K, Blettner M, et al. Environmental risk factors for sporadic acoustic neuroma (Interphone Study Group, Germany). EUROPEAN JOURNAL OF CANCER. 2007;43(11):1741-1747