Ad
related to: pyridinium salts properties and structure formula chemistry class 11 book
Search results
Results from the WOW.Com Content Network
Its salts are often insoluble in the organic solvent, so precipitation of the pyridinium leaving group complex is an indication of the progress of the reaction. Pyridinium cations are aromatic, as determined through Hückel's rule. [4] They are isoelectronic with benzene.
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.
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).
The Cornforth reagent (pyridinium dichromate or PDC) is a pyridinium salt of dichromate with the chemical formula [C 5 H 5 NH] 2 [Cr 2 O 7].This compound is named after the Australian-British chemist Sir John Warcup Cornforth (b. 1917) who introduced it in 1962.
Pyridinium chlorochromate in a vial. Pyridinium chlorochromate (PCC) is a yellow-orange salt with the formula [C 5 H 5 NH] + [CrO 3 Cl] −. It is a reagent in organic synthesis used primarily for oxidation of alcohols to form carbonyls. A variety of related compounds are known with similar reactivity.
The second family of reagents are salts, featuring the pyridinium cation (C 5 H 5 NH +). pyridinium dichromate (PDC) is the pyridium salt of dichromate, [Cr 2 O 7] 2-. pyridinium chlorochromate (PCC) is the pyridinium salt of [CrO 3 Cl] −. These salts are less reactive, more easily handled, and more selective than Collins reagent in ...
The reaction of pyridine with bromomethyl ketones gives the related pyridinium salt, wherein the methylene group is highly acidic. This species undergoes a Michael-like addition to α,β-unsaturated carbonyls in the presence of ammonium acetate to undergo ring closure and formation of the targeted substituted pyridine as well as pyridinium ...
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 ...
Ad
related to: pyridinium salts properties and structure formula chemistry class 11 book