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  2. Pyridinium - Wikipedia

    en.wikipedia.org/wiki/Pyridinium

    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.

  3. Pyridinium p-toluenesulfonate - Wikipedia

    en.wikipedia.org/wiki/Pyridinium_p-toluenesulfonate

    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.

  4. Zincke reaction - Wikipedia

    en.wikipedia.org/wiki/Zincke_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).

  5. Pyridine - Wikipedia

    en.wikipedia.org/wiki/Pyridine

    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 ...

  6. Pyridinium perbromide - Wikipedia

    en.wikipedia.org/wiki/Pyridinium_perbromide

    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 ...

  7. Japan's SoftBank plans to invest $100 billion in US projects ...

    www.aol.com/trump-announce-100b-softbank...

    President-elect Donald Trump joined SoftBank Group CEO Masayoshi Son to announce plans by the Japanese company to invest $100 billion in U.S. projects over the next four years. Trump announced the ...

  8. 2,6-Pyridinedicarbothioic acid - Wikipedia

    en.wikipedia.org/wiki/2,6-Pyridinedicarbothioic_acid

    This route produces the pyridinium salt of pyridinium-2,6-dicarbothioate. Treatment of this orange-colored salt with sulfuric acid gives colorless PDTC, which can then be extracted with dichloromethane. [2] The biosynthesis of PDTC remains unclear although some insights can be deduced from the genetics. [3]

  9. Gabriel Jesus' knee injury is a 'big worry' to Arsenal ... - AOL

    www.aol.com/gabriel-jesus-carried-off-stretcher...

    Arsenal manager Mikel Arteta said there was a “big worry” over Gabriel Jesus after the striker was carried off on a stretcher with a knee injury during the first half of the FA Cup loss to ...