High enantioselectivity (up to 98 % ee) has been achieved for the conjugate addition of diethylzinc to acyclic enones utilizing Cu(I) complexes of the novel chiral P,N ligands 1. The high enantioselectivities are best achieved using [Cu(OTf)](2) small middle dotC(6)H(6) as the copper catalyst precursor in nonpolar solvents such as toluene or Cl(CH(2))(2)Cl. R=H, CH(3); Tf=F(3)CSO(2).

A new Cu-catalyzed efficient protocol is described for the transformation of oximes to the corresponding carbonate derivatives. Diisopropyl azodicarboxylate acted as a selective new precursor for the synthesis of oxime carbonates in high yields. The O-H bond cleavage and O-C bond formation occur in the presence of a copper catalyst providing a synthetically useful process, which tolerates a wid...

The first example of a general asymmetric nitrosocarbonyl hetero-ene reaction is described. The procedure uses a copper-catalyzed aerobic oxidation of a commercially available chiral nitrosocarbonyl precursor (EleNOr) and is operationally simple. The transformation is both high yielding and highly diastereoselective for a range of silyl enol ether derivatives. A variety of synthetically useful ...

Galactose oxidase (EC ) is a monomeric enzyme that contains a single copper ion and catalyses the stereospecific oxidation of primary alcohols to their corresponding aldehydes. The protein contains an unusual covalent thioether bond between a tyrosine, which acts as a radical center during the two-electron reaction, and a cysteine. The enzyme is produced in a precursor form lacking the thioethe...

Possible precursor complexes for the aerobic oxidation of benzene to phenol in CuHY zeolites were studied by QM/MM calculations. Structures limited to just one copper center were determined, in which both, benzene and dioxygen are adsorbed to and activated by the same transition metal cation. Frequency analyses reveal that these complexes can be identified by the frequency shift of the O(2) str...

surface ozone (surface o3)is a secondary pollutant and there are only limited studies on ozone in south india. studies have revealed a strong correlation between higher ozone levels and warmer days. surface o3 along with its precursors like no2, co and ch4 are being measured at kanyakumari (8.0780° n, 77.5410° e), tamilnadu, india and in this paper we present the summer time variation of ozone ...

Carbon materials have attracted increasing attention as supports for metal catalysts. Iron-containing carbon nanotubes often promoted with copper found application in Fischer-Tropsch synthesis, which provides an alternative way conversion of renewable feedstocks to chemicals and fuels. In nanotubes, the active phase can be nanoconfined inside channels or localized on outer surface. most previou...