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Chemical formula. C 12 H 13 N O 3 S: Molar mass: ... Pyridinium p-toluenesulfonate (PPTS) is a colourless solid salt of pyridine and p-toluenesulfonic acid.
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.
The formation of the DNP-pyridinium salt. Upon heating a primary amine with the N-2,4-dinitrophenyl-pyridinium salt (2), the addition of the amine leads to the opening of the pyridinium ring. A second addition of amine leads to the displacement of 2,4-dinitroaniline (5) and formation of the König salt [5] (6a and 6b).
p-Toluenesulfonic acid (PTSA, pTSA, or pTsOH) or tosylic acid (TsOH) is an organic compound with the formula CH 3 C 6 H 4 SO 3 H. It is a white extremely hygroscopic solid that is soluble in water, alcohols, and other polar organic solvents. [6] The CH 3 C 6 H 4 SO 2 group is known as the tosyl group and is often abbreviated as Ts or Tos.
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 ...
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. Hence they are stronger acids than ...
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 ...
1,3-dicarbonyl compounds have also been shown to be viable starting materials in place of the α-pyridinium methyl ketone salts. [7] For example, treatment of 1,3-diketone 14 with base in ethanol followed by ammonium acetate, acetic acid, the corresponding enone and a Lewis acid yields 3-acyltriarylpyridines of the form 15.