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  2. Enamine - Wikipedia

    en.wikipedia.org/wiki/Enamine

    The general structure of an enamine. An enamine is an unsaturated compound derived by the condensation of an aldehyde or ketone with a secondary amine. [1] [2] Enamines are versatile intermediates. [3] [4] Condensation to give an enamine. [5] The word "enamine" is derived from the affix en-, used as the suffix of alkene, and the root amine.

  3. Hantzsch pyrrole synthesis - Wikipedia

    en.wikipedia.org/wiki/Hantzsch_pyrrole_synthesis

    The mechanism starts with the amine (1) attacking the β carbon of the β-ketoesters (2), and eventually forming an enamine (3). The enamine then attacks the carbonyl carbon of the α-haloketone (4). This is followed by the loss of H 2 O, giving an imine (5).

  4. Amidine - Wikipedia

    en.wikipedia.org/wiki/Amidine

    Amidines are much more basic than amides and are among the strongest uncharged/unionized bases. [6] [7] Protonation occurs at the sp 2-hybridized nitrogen. This occurs because the positive charge can be delocalized onto both nitrogen atoms. The resulting cationic species is known as an amidinium ion [8] and possesses identical C-N bond lengths.

  5. Reductive amination - Wikipedia

    en.wikipedia.org/wiki/Reductive_amination

    Reductive amination (also known as reductive alkylation) is a form of amination that converts a carbonyl group to an amine via an intermediate imine. The carbonyl group is most commonly a ketone or an aldehyde. It is a common method to make amines and is widely used in green chemistry since it can be done catalytically in one-pot under

  6. Mannich reaction - Wikipedia

    en.wikipedia.org/wiki/Mannich_reaction

    In organic chemistry, the Mannich reaction is a three-component organic reaction that involves the amino alkylation of an acidic proton next to a carbonyl (C=O) functional group by formaldehyde (H−CHO) and a primary or secondary amine (−NH 2) or ammonia (NH 3). [1] The final product is a β-amino-carbonyl compound also known as a Mannich base.

  7. Imine - Wikipedia

    en.wikipedia.org/wiki/Imine

    In recent years, several reagents such as Tris(2,2,2-trifluoroethyl)borate [B(OCH 2 CF 3) 3], [14] pyrrolidine [15] or titanium ethoxide [Ti(OEt) 4] [16] have been shown to catalyse imine formation. Rarer than primary amines is the use of ammonia to give a primary imine. [17] In the case of hexafluoroacetone, the hemiaminal intermediate can be ...

  8. Is It Safe to Use Expired Vitamins? The Truth About Vitamin ...

    www.aol.com/vitamins-expire-nutritionists-weigh...

    When you buy a bottle of vitamins from a nutrition store, you’ll probably notice a best-by date on the bottom of the jar. But that inscribed number isn’t a hard-and-fast rule—there is some ...

  9. Forster–Decker method - Wikipedia

    en.wikipedia.org/wiki/Forster–Decker_method

    The Forster–Decker method is a series of chemical reactions that have the effect of mono-alkylating a primary amine (1), forming a secondary amine (6). [1] [2] The process occurs by way of transient formation of an imine (3) that undergoes the actual alkylation reaction.