Selenium

Base Information

• Chemical Name: Selenium
• CAS No.: 7782-49-2
• Deprecated CAS: 11125-23-8,11133-88-3,12640-29-8,12640-30-1,12641-96-2,12733-65-2,37256-19-2,37258-85-8,37276-15-6,37368-02-8,50954-17-1,51882-60-1,95788-45-7,11133-88-3,12640-29-8,12640-30-1,12641-96-2,12733-65-2,37256-19-2,37258-85-8,37276-15-6,37368-02-8,50954-17-1,51882-60-1,95788-45-7
• Molecular Formula: Se
• Molecular Weight: 78.96
• Hs Code.: 28049090
• European Community (EC) Number: 231-957-4
• ICSC Number: 0072
• UN Number: 3283,2658
• UNII: H6241UJ22B,V91P54KPAM
• DSSTox Substance ID: DTXSID9021261
• Wikipedia: Selenium
• Wikidata: Q876
• NCI Thesaurus Code: C825
• RXCUI: 9641
• ChEMBL ID: CHEMBL1235891
• Mol file: 7782-49-2.mol

Synonyms:hydrogen selenide;hydrogen selenide, 75Se-labeled;selane;Selenium;Selenium 80;Selenium-80

Chemical Property of Selenium

Chemical Property:

• Appearance/Colour: dark grey to dark red powder or crystals
• Vapor Pressure: <1 Pa (20 °C)
• Melting Point: 217 °C(lit.)
• Boiling Point: 684.9 °C(lit.)
• PSA: 0.00000
• Density: 4.81 g/cm³
• LogP: 0.00000
• Storage Temp.: Storage temperature: no restrictions.
• Solubility.: H2O: soluble
• Water Solubility.: Insoluble
• Hydrogen Bond Donor Count: 0
• Hydrogen Bond Acceptor Count: 0
• Rotatable Bond Count: 0
• Exact Mass: 79.91652
• Heavy Atom Count: 1
• Complexity: 0
• Transport DOT Label: Poison

Purity/Quality:

99.0% ^*data from raw suppliers

SeleniumShot ^*data from reagent suppliers

Safty Information:

• Hazard Codes: T
• Statements: 36/38-53-33-23/25
• Safety Statements: 26-61-45-28-20/21-28A

MSDS Files:

SDS file from LookChem

Total 1 MSDS from other Authors

Useful:

• Chemical Classes: Other Classes -> Other Inorganic Compounds
• Canonical SMILES: [Se]
• Recent ClinicalTrials: Evaluation of the Relationship Between Serum Selenium Level and Glycemic Control in Pregnant Patients*
• Recent EU Clinical Trials: HIGH DOSE SUPPLEMENTATION OF SELENIUM IN LEFT VENTRICULAR ASSIST DEVICE (LVAD) IMPLANT SURGERY – A DOUBLE BLIND RANDOMISED CONTROLLED TRIAL
• Recent NIPH Clinical Trials: Clinical trial of sodium selenite in patient with selenium deficiency
• Inhalation Risk: A harmful concentration of airborne particles can be reached quickly on spraying or when dispersed, especially if powdered.
• Effects of Short Term Exposure: The substance is irritating to the respiratory tract. The substance may cause effects on the gastrointestinal tract and nervous system.
• Effects of Long Term Exposure: The substance may have effects on the respiratory tract, gastrointestinal tract and skin.
• Physical Properties: Selenium exists in several allotropic forms. Three distinct forms are (1)amorphous (2)crystalline and (3)metallic: Amorphous forms exhibit two colors, occurring as a red powder of density 4.26g/cm3 that has a hexagonal crystal structure and a black vitreous solid of density 4.28g/cm3. The red amorphous selenium converts to the black form on standing. Amorphous selenium melts at 60 to 80°C; insoluble in water; reacts with water at 50°C when freshly precipitated; soluble in sulfuric acid, benzene and carbon disulfide. Crystalline selenium exhibits two monoclinic forms: an alpha form constituting dark red transparent crystals, density 4.50 g/cm3. The alpha form converts to a metastable beta form of hexagonal crystal structure when heated to about 170°C. Both the crystalline forms are insoluble in water; soluble in sulfuric and nitric acids; very slightly soluble in carbon disulfide. Also, both the crystalline forms convert into gray metallic modification on heating. The gray metallic form of selenium is its most stable modification. It constitutes lustrous gray to black hexagonal crystals; density 4.18 g/cm3 at 20°; melts at 217°C; soluble in sulfuric acid and chloroform; very slightly soluble in carbon disulfide; insoluble in alcohol. All forms of selenium vaporize at 684.8°C.
• Description: Selenium was discovered in 1817 by J?ns Jacob Berzelius. Especially noted was the similarity of the new element to the previously known tellurium. Selenium is an essential trace element atw0.1 ppm in diets. Selenium is a biologically active part of a number of important proteins, particularly enzymes involved in antioxidant defense mechanisms, thyroid hormone metabolism, and redox control of intracellular reactions. In humans and animals, selenium plays a role in protecting tissues from oxidative damage as a component of glutathione peroxidase.
• Physical properties: Selenium is a soft metalloid or semimetal that is similar to tellurium, located just belowit in the oxygen group, and sulfur, which is just above it in the same group. Selenium hasseveral allotropic forms that range from a gray metallic appearance to a red glassy appearance.These allotropic forms also have different properties of heat, conductivity, and density. In itsamorphous state, it is a red powder that turns black and becomes crystalline when heated.Crystalline selenium has a melting point of 220°C, a boiling point of 685°C, and a densityof 4.809 g/cm3.
• Uses: selenium is a trace mineral used for years in topical preparations for its anti-fungal properties. Selenium has been shown to have other protective effects such as repairing DnA, reducing the DnA-binding of carcinogens, and suppressing gene mutations. In laboratory studies, skin lotions containing selenium compounds have been shown to decrease uV-induced skin damage such as inflammation, blistering, and pigmentation. Selenium is used in the manufacture of colored glass, in photocells, in semiconductors,as a rectifier in radio and television sets, andas a vulcanizing agent in the manufacture ofrubber.Klaus Schwartz in 1957 discovered thattrace amounts of selenium in the feed protectedvitamin E-deficient rats from dietaryliver necrosis. Soon, thereafter, several animaland epidemiology studies showed thatits presence in the diet could provide protectiveaction in humans against several degenerativediseases including cirrhosis, cancer,diabetes and Keshan disease, a juvenile cardiomyopathy.The range between its beneficialand toxic character, however, is veryclose and, therefore, the daily dietary intakeshould be appropriately monitored (Naverro-Alarcon and Lopez-Martinez 2000). Thereis no accurate estimate of human requirementsof dietary selenium. Extrapolation ofanimal data to humans suggest an averagedaily requirement in the range 50 to 200 μg.Longnecker et al. (1991) observed no evidenceof adverse effects from selenium inhuman health at a daily intake level as highas 724 μg.. The photosensitive nature of selenium makes it useful in devices that respond to theintensity of light, such as photocells, light meters for cameras, xerography, and electric “eyes.”Selenium also has the ability to produce electricity directly from sunlight, making it ideal foruse in solar cells. Selenium possesses semiconductor properties that make it useful in the electronicsindustry, where it is a component in some types of solid-state electronics and rectifiers.It is also used in the production of ruby-red glass and enamels and as an additive to improvethe quality of steel and copper. Additionally, it is a catalyst (to speed up chemical reactions)in the manufacture of rubber.Selenium is an essential trace element for both plants and animals, and it is a diet supplementin animal feed as well as for humans.

Technology Process of Selenium

There total 446 articles about Selenium which guide to synthetic route it. The literature collected by LookChem mainly comes from the sharing of users and the free literature resources found by Internet computing technology. We keep the original model of the professional version of literature to make it easier and faster for users to retrieve and use. At the same time, we analyze and calculate the most feasible synthesis route with the highest yield for your reference as below:

synthetic route:

Reference yield: 62.0%

hydrogenchloride (7647-01-0,15364-23-5) + potassium ferrocenecarboselenoate → selenium (7782-49-2) + diferrocenoyl selenide (779339-32-1) + diferrocenoyl diselenide (779339-31-0)

Guidance literature:

With air; In tetrahydrofuran; at 21 - 25 ℃; for 24h;

DOI:10.1002/zaac.201200369

Reference yield:

diselenium dichloride (10025-68-0) + silicon (7440-21-3) → selenium (7782-49-2) + tetrachlorosilane (10026-04-7,53609-55-5)

Guidance literature:

In neat (no solvent);

Reference yield:

antimony(III) sulfide + diselenium dichloride (10025-68-0) → selenium (7782-49-2) + antimony(III) chloride (10025-91-9) + sulfur (7704-34-9)

Guidance literature:

In neat (no solvent); 100 °C;;

upstream raw materials:

potassium carbonate

diselenium dichloride

selenide

tellurite^(2-)

Downstream raw materials:

potassium selenide

diselenium dibromide

selenium(IV) oxide

selenious acid

Refernces

3,4-DICHALCOGEN-BRIDGED FLUORANTHENES AS NEW ELECTRON DONORS

10.1016/S0040-4039(00)84435-4

The research aimed to develop new electron donors by synthesizing three 3,4-dichalcogen-bridged fluoranthenes, with the donor strength increasing in the order of the chalcogen triad: sulfur, selenium, and tellurium. The study focused on polycyclic aromatic compounds with peri-dichalcogen bridges, which are known for their electron-donating properties. The researchers synthesized fluorantheno[3,4-cdl-1,2-dithiole], -diselenole, and -ditellurole, using a multistage pathway starting with acenaphthene and involving various chemical reactions such as chlorination, dehydrogenation, bromination, and Diels-Alder reactions. The synthesized compounds were characterized by elemental and spectroscopic analyses, and their electronic spectra and cyclic voltammetry results indicated an enhanced electronic interaction between the fluoranthene and the heavy chalcogen, which strengthened the donor character.

Synthesis and Multinuclear Magnetic Resonance Study of Para-Substituted Phenyl Selenobenzoates

10.1021/jo00206a017

The study investigates the synthesis and spectroscopic properties of a series of para-substituted Se-phenyl selenobenzoates. The researchers synthesized eleven compounds, including NO2, CN, C(O)CH3, C(O)OCH2CH3, F, Cl, Br, CH3, OCH3, and N(CH3)2 as substituents. The primary goal was to systematically evaluate the 77Se and 13C NMR chemical shifts, coupling constants, and infrared carbonyl absorption frequencies of these compounds. The study found that mesomeric substituents strongly interact with the aromatic ring, and the SeC(0)Ph moiety is electron-deficient relative to the substituted benzene. The results provide valuable data for understanding the electronic effects of various substituents on selenol esters, which is crucial for further applications in biomolecular studies involving selenium.