Search results
Results from the WOW.Com Content Network
Tetrakis(triphenylphosphine)palladium(0) (sometimes called quatrotriphenylphosphine palladium) is the chemical compound [Pd(P(C 6 H 5) 3) 4], often abbreviated Pd(PPh 3) 4, or rarely PdP 4. It is a bright yellow crystalline solid that becomes brown upon decomposition in air .
Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C 6 H 5) 3 and often abbreviated to P Ph 3 or Ph 3 P. It is versatile compound that is widely used as a reagent in organic synthesis and as a ligand for transition metal complexes, including ones that serve as catalysts in organometallic chemistry.
[1] [2] A variety of nickel catalysts in either Ni 0 or Ni II oxidation state can be employed in Negishi cross couplings such as Ni(PPh 3) 4, Ni(acac) 2, Ni(COD) 2 etc. [3] [4] [5] The leaving group X is usually chloride, bromide, or iodide, but triflate and acetyloxy groups are feasible as well. X = Cl usually leads to slow reactions.
A purple sea urchin being tested for pollution using a whole effluent toxicity method.. Aquatic toxicology is the study of the effects of manufactured chemicals and other anthropogenic and natural materials and activities on aquatic organisms at various levels of organization, from subcellular through individual organisms to communities and ecosystems. [1]
This indicates that TPhP may be present in the environment at high enough concentrations to have harmful ecological effects. [11] The European Chemicals agency considers TPhP to be "very toxic" to aquatic life, with potentially long-lasting effects. [12] In contrast to many persistent organic pollutants, TPHP has limited affinity for lipids.
While marine pollution can be obvious, as with the marine debris shown above, it is often the pollutants that cannot be seen that cause most harm.. Marine pollution occurs when substances used or spread by humans, such as industrial, agricultural and residential waste, particles, noise, excess carbon dioxide or invasive organisms enter the ocean and cause harmful effects there.
Diagram depicting the sources and cycles of acid rain precipitation. Freshwater acidification occurs when acidic inputs enter a body of fresh water through the weathering of rocks, invasion of acidifying gas (e.g. carbon dioxide), or by the reduction of acid anions, like sulfate and nitrate within a lake, pond, or reservoir. [1]
Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula P H 3, classed as a pnictogen hydride.Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting fish, due to the presence of substituted phosphine and diphosphane (P 2 H 4).