Search results
Results from the WOW.Com Content Network
Containing a pyridinium ion, pyridinium chloride has a pK a of approximately 5, slightly more acidic than that of typical amines.This is due to the hybridization of the nitrogen: the nitrogen is sp 2 hybridized and more electronegative than those nitrogens in ammonium cations, which are sp 3 hybridized.
Pyridine is a basic heterocyclic organic compound with the chemical formula C 5 H 5 N. It is structurally related to benzene, with one methine group (=CH−) replaced by a nitrogen atom (=N−). It is a highly flammable, weakly alkaline, water-miscible liquid with a distinctive, unpleasant fish
They are prepared by treating pyridine with acids. [3] As pyridine is often used as an organic base in chemical reactions, pyridinium salts are produced in many acid-base reactions. 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.
Cr(VI)-pyridine and pyridinium reagents have the advantage that they are soluble in organic solvents as are the alcohol substrates. One family of reagents employs the complex CrO 3 (pyridine) 2. [2] Sarett's reagent: a solution of CrO 3 (pyridine) 2 in pyridine. It was popularized for selective oxidation of primary and secondary alcohols to ...
2-Chloropyridine reacts with nucleophiles to generate pyridine derivatives substituted at the second and fourth carbons on the heterocycle. Therefore, many reactions using 2-chloropyridine generate mixtures of products which require further workup to isolate the desired isomer.
Direct halogenation of pyridine with chlorine gas above 270 °C gives a mixture of 2-chloropyridine and 2,6-dichloropyridine. [1] 2- and 4-chloropyridine are prepared from the corresponding pyridinols using phosphoryl chloride. [1]
In chemistry, thermochemical cycles combine solely heat sources (thermo) with chemical reactions to split water into its hydrogen and oxygen components. [1] The term cycle is used because aside of water, hydrogen and oxygen, the chemical compounds used in these processes are continuously recycled.
Transition metal pyridine complexes encompass many coordination complexes that contain pyridine as a ligand. Most examples are mixed-ligand complexes. Most examples are mixed-ligand complexes. Many variants of pyridine are also known to coordinate to metal ions, such as the methylpyridines, quinolines, and more complex rings.