Alcohols, trimethylsilyl ethers and thiols were efficiently converted to their corresponding carbonyl and disulfides compounds using o-xylylenebis (triphenylphosphonium) dibromochromate (XTPPDBC). This reagent can selectively oxidize thiols to disulfides in the presence of alcohols and trimethylsilyl ethers in acetonitrile at room temperature.

Samples of the waste rock obtained from Marofengin South Africa ground 60, 70 and 80% passing 75µm were leached with cyanide in bottle roll tests. The results obtained showed that the percentage gold dissolution depends more on the ore size consists than on the cyanide concentration with the highest average dissolution rates of 88.75, 94.34 and 95.90% found at 600, 500 and 500 ppm, for 60, ...

The very low basicity and nucleophilicity of the phosphorus donor in phosphinines can be drastically increased by introducing strongly σ-donating Me3Si substituents to aromatic heterocycle. highest gas-phase was found for 2,3,5,6-tetrakis(trimethylsilyl)phosphinine, which is even more basic gas phase than pyridine. This finding led first quantitative synthesis a phosphinine selenide treating re...

Background: Besides acute lethal cyanide poisoning, its chronic intoxication may also produce some pathologic effects on different tissues that precedes alterations in biochemical parameters. The present study was aimed to evaluate the effects of sublethal cyanide exposure on some tissue enzyme activities in liver and kidney of rats. Methods: Twelve male rats were divided into two groups as ...

Nitrilases have a high potential for application in organic chemistry, environmental technology, and analytics. However, their industrial uses require that they are produced highly active robust forms at reasonable cost. Some syntheses catalyzed by nitrilases already reached level of technological readiness. This has been enabled the large-scale production recombinant catalysts. Despite some pr...

Tris(trimethylsilyl)silane (TTMSS) and azobisisobutironitrile (AIBN) promote the intramolecular heteroarylation of arenesulfonamides with pyridyl radicals under thermal conditions. The arenesulfonamides are easily prepared from pyridinium N-2 0pyridylaminide. The heteroarylation process involves pyridyl radical cyclization and ipso substitution. q 2004 Elsevier Ltd. All rights reserved.