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  2. Acid anhydride - Wikipedia

    en.wikipedia.org/wiki/Acid_anhydride

    An acid anhydride is a type of chemical compound derived by the removal of water molecules from an acid. In organic chemistry, organic acid anhydrides contain the functional group −C(=O)−O−C(=O)−. Organic acid anhydrides often form when one equivalent of water is removed from two equivalents of an organic acid in a dehydration reaction.

  3. Acetic anhydride - Wikipedia

    en.wikipedia.org/wiki/Acetic_anhydride

    Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula (CH 3 CO) 2 O. Commonly abbreviated Ac 2 O, it is the simplest isolable anhydride of a carboxylic acid and is widely used as a reagent in organic synthesis. It is a colorless liquid that smells strongly of acetic acid, which is formed by its reaction with ...

  4. Di-tert-butyl dicarbonate - Wikipedia

    en.wikipedia.org/wiki/Di-tert-butyl_dicarbonate

    European and Japanese companies use the reaction of sodium tert-butoxide with carbon dioxide, catalysed by p-toluenesulfonic acid or methanesulfonic acid. This process involves a distillation of the crude material yielding a very pure grade. Boc anhydride is also available as a 70% solution in toluene or THF. As boc anhydride may melt at ...

  5. Fischer–Speier esterification - Wikipedia

    en.wikipedia.org/wiki/Fischer–Speier...

    The reaction is often carried out without a solvent (particularly when a large reagent excess of the alcohol reagent is used) or in a non-polar solvent (e.g. toluene, hexane) that can facilitate Dean–Stark distillation to remove the water byproduct. [4] Typical reaction times vary from 1–10 hours at temperatures of 60–110 °C.

  6. Shiina macrolactonization - Wikipedia

    en.wikipedia.org/wiki/Shiina_macrolactonization

    Shiina macrolactonization (or Shiina lactonization) is an organic chemical reaction that synthesizes cyclic compounds by using aromatic carboxylic acid anhydrides as dehydration condensation agents. In 1994, Prof. Isamu Shiina ( Tokyo University of Science , Japan) reported an acidic cyclization method using Lewis acid catalyst , [ 1 ] [ 2 ...

  7. Organic acid anhydride - Wikipedia

    en.wikipedia.org/wiki/Organic_acid_anhydride

    A common type of organic acid anhydride is a carboxylic anhydride, where the parent acid is a carboxylic acid, the formula of the anhydride being (RC(O)) 2 O. Symmetrical acid anhydrides of this type are named by replacing the word acid in the name of the parent carboxylic acid by the word anhydride. [2] Thus, (CH 3 CO) 2 O is called acetic ...

  8. Friedel–Crafts reaction - Wikipedia

    en.wikipedia.org/wiki/Friedel–Crafts_reaction

    The reaction proceeds through generation of an acylium center. The reaction is completed by deprotonation of the arenium ion by AlCl 4 −, regenerating the AlCl 3 catalyst. However, in contrast to the truly catalytic alkylation reaction, the formed ketone is a moderate Lewis base, which forms a complex with the strong Lewis acid aluminum ...

  9. Shiina esterification - Wikipedia

    en.wikipedia.org/wiki/Shiina_Esterification

    To balance the reaction, each TFBA accepts the atoms of one water molecule from its starting materials, i.e., the carboxylic acid and alcohol, and then changes itself into two molecules of 4-trifluoromethylbenzoic acid at the end of the reaction. Since the Lewis acid catalyst is reproduced at the end of the reaction, only a small proportion of ...