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Selenium compounds commonly exist in the oxidation states −2, +2, +4, and +6. It is a nonmetal (more rarely considered a metalloid ) with properties that are intermediate between the elements above and below in the periodic table , sulfur and tellurium , and also has similarities to arsenic .
The selenium starting material is reduced to selenium, and precipitates as a red amorphous solid which can easily be filtered off. [10] This type of reaction is called a Riley oxidation. It is also renowned as a reagent for allylic oxidation, [11] a reaction that entails the following conversion Allylic oxidation. This can be described more ...
[1] [2] [3] Selenium belongs with oxygen and sulfur to the group 16 elements or chalcogens, and similarities in chemistry are to be expected. Organoselenium compounds are found at trace levels in ambient waters, soils and sediments. [4] Selenium can exist with oxidation state −2, +2, +4, +6. Se(II) is the dominant form in organoselenium ...
Among these compounds, selenium has various oxidation states, the most common ones being −2, +4, and +6. Selenium compounds exist in nature in the form of various minerals, such as clausthalite, guanajuatite, tiemannite, crookesite etc., and can also coexist with sulfide minerals such as pyrite and chalcopyrite. [1]
Selenium's oxidation states are −2, +4, and +6. Selenium, like most chalcogens, bonds with oxygen. [2] There are some organic selenium compounds, such as selenoproteins. Tellurium's oxidation states are −2, +2, +4, and +6. [6] Tellurium forms the oxides tellurium monoxide, tellurium dioxide, and tellurium trioxide. [2] Polonium's oxidation ...
The Riley oxidation is a selenium dioxide-mediated oxidation of methylene groups adjacent to carbonyls. It was first reported by Harry Lister Riley and co-workers in 1932. [ 1 ] In the decade that ensued, selenium -mediated oxidation rapidly expanded in use, and in 1939, Andre Guillemonat and co-workers disclosed the selenium dioxide-mediated ...
The oxidation states are also maintained in articles of the elements (of course), and systematically in the table {{Infobox element/symbol-to-oxidation-state}} See also [ edit ]
Selenomethionine (SeMet) is a naturally occurring amino acid.The L-selenomethionine enantiomer is the main form of selenium found in Brazil nuts, cereal grains, soybeans, and grassland legumes, while Se-methylselenocysteine, or its γ-glutamyl derivative, is the major form of selenium found in Astragalus, Allium, and Brassica species. [1]