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Pyridinium perbromide (also called pyridinium bromide perbromide, pyridine hydrobromide perbromide, or pyridinium tribromide) is an organic chemical composed of a pyridinium cation and a tribromide anion. It can also be considered as a complex containing pyridinium bromide—the salt of pyridine and hydrogen bromide—with an added bromine (Br ...
Tribromide is the anion with the chemical formula Br 3 −, or salts containing it: . Tetrabutylammonium tribromide; Tetrabromophosphonium tribromide; Pyridinium perbromide; Sodium and potassium tribromides can be prepared by reacting NaBr or KBr with aqueous bromine.
Pyridinium refers to the cation [C 5 H 5 NH] +. It is the conjugate acid of pyridine . Many related cations are known involving substituted pyridines, e.g. picolines, lutidines, collidines.
In organic synthesis, PPTS is used as a weakly acidic catalyst, providing an organic soluble source of pyridinium (C 5 H 5 NH +) ions. For example, PPTS is used to deprotect silyl ethers or tetrahydropyranyl ethers when a substrate is unstable to stronger acid catalysts.
Phosphorus tribromide, like PCl 3 and PF 3, has both properties of a Lewis base and a Lewis acid. For example, with a Lewis acid such as boron tribromide it forms stable 1 :1 adducts such as Br 3 B · PBr 3. At the same time PBr 3 can react as an electrophile or Lewis acid in many of its reactions, for example with amines.
Bromoantimonates can have antimony in one of two oxidation states, either +3 or +5.These are designated by bromoantimonate(III) or bromoantimonate(V). Although antimony tribromide is known, SbBr 5 on its own does not exist, despite the existence of SbBr − 6. [1]
In a letter to Angewandte Chemie, the German chemist Manfred Christl [14] pointed out not only that the alleged new chemistry was in fact 100-year-old Zincke chemistry but also that the proposed structure for the reaction product was not the 12 membered ring but the 6 membered pyridinium salt (structure 2).
Toggle the table of contents. ... Bismuth tribromide is an inorganic compound of bismuth and bromine with the chemical formula BiBr 3.