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Sodium benzeneselenolate; Trimethylsilyl phenyl selenide; The most common oxidizing agent employed is hydrogen peroxide (H 2 O 2). [9] It is sometimes used in excess, to overcome catalytic decomposition of H 2 O 2 by selenium; however, undesired oxidation of starting material has been observed under these conditions.
At higher pH, selenide forms. Solutions of hydrogen selenide and selenide are oxidized by air to give elemental selenium: 2 SeH − + O 2 → 2 Se + 2 OH −. Most elements form selenides. They sometimes have salt-like properties, e.g. sodium selenide, but most exhibit covalent bonding, e.g. molybdenum diselenide. Their properties are diverse ...
Sodium selenide is an inorganic compound of sodium and selenium with the chemical formula Na 2 Se. Preparation. This colourless solid is prepared by the reaction of ...
In presence of a β-hydrogen, a selenide will give an elimination reaction after oxidation, to leave behind an alkene and a SeO-selenoperoxol. The SeO-selenoperoxol is highly reactive and is not isolated as such. In the elimination reaction, all five participating reaction centers are coplanar and, therefore, the reaction stereochemistry is syn.
A reaction characteristic of Ph 2 Se 2 is its reduction: . Ph 2 Se 2 + 2 Na → 2 PhSeNa. PhSeNa is a useful nucleophile used to introduce the phenylselenyl group by nucleophilic substitution of alkyl halides, alkyl sulfonates (mesylates or tosylates) and epoxides.
More so than thiophenol, benzeneselenol is easily oxidized by air. The facility of this reaction reflects the weakness of the Se-H bond, bond dissociation energy of which is estimated to be between 67 and 74 kcal/mol. [1] In contrast, the S-H BDE for thiophenol is near 80 kcal/mol. [3] The product is diphenyl diselenide as shown in this idealized equation:
A hydroselenide (or biselenide or selanide) is an ion or chemical compound containing the [SeH] − ion. The radical HSe is a pseudohalogen.Hydroselenide can be a ligand in transition metal complexes where it can be attached to a single atom, or bridge two atoms.
Sodium hydroselenide is an inorganic compound with the chemical formula Na Se H. It is a salt of hydrogen selenide. It consist of sodium cations Na + and hydroselenide anions − SeH. Each unit consists of one sodium, one selenium, and one hydrogen atom. Sodium hydroselenide is a selenium analog of sodium hydroxide NaOH.