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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. 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 ...

  5. Oxidation with chromium(VI) complexes - Wikipedia

    en.wikipedia.org/wiki/Oxidation_with_chromium(VI...

    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 ...

  6. Pyridinium chlorochromate - Wikipedia

    en.wikipedia.org/wiki/Pyridinium_chlorochromate

    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.

  7. A pink powder is being used to fight California fires. It's ...

    www.aol.com/pink-powder-being-used-fight...

    The exact formula of Phos-Chek is not public knowledge but the company has said in previous filings that the product is 80% water, 14% fertiliser-type salts, 6% colouring agents and corrosion ...

  8. 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 ...

  9. How to Reset These 10 Hormones That Affect Weight This Year - AOL

    www.aol.com/reset-10-hormones-affect-weight...

    How to Reset Female Hormones For Weight Loss. This article was reviewed by Craig Primack, MD, FACP, FAAP, MFOMA. Hormones can be helpful heroes, supporting the immune system and a healthy sleep ...