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  2. Horner–Wadsworth–Emmons reaction - Wikipedia

    en.wikipedia.org/wiki/HornerWadsworthEmmons...

    The HornerWadsworthEmmons (HWE) reaction is a chemical reaction used in organic chemistry of stabilized phosphonate carbanions with aldehydes (or ketones) to produce predominantly E-alkenes. [1] The HornerWadsworthEmmons reaction. In 1958, Leopold Horner published a modified Wittig reaction using phosphonate-stabilized carbanions.

  3. Wittig reaction - Wikipedia

    en.wikipedia.org/wiki/Wittig_reaction

    To obtain the (E)-alkene for unstabilized ylides, the Schlosser modification of the Wittig reaction can be used. Alternatively, the Julia olefination and its variants also provide the (E)-alkene selectively. Ordinarily, the HornerWadsworthEmmons reaction provides the (E)-enoate

  4. Wittig reagents - Wikipedia

    en.wikipedia.org/wiki/Wittig_reagents

    It is however less reactive than ylides lacking EWGs. For example they usually fail to react with ketones, necessitating the use of the HornerWadsworthEmmons reaction as an alternative. Such stabilized ylides usually give rise to an E-alkene product when they react, rather than the more usual Z-alkene. A "stabilized" Wittig reagent.

  5. Oxaphosphetane - Wikipedia

    en.wikipedia.org/wiki/Oxaphosphetane

    1,2-Oxaphosphetanes are rarely isolated but are important intermediates in the Wittig reaction and related reactions such as the Seyferth–Gilbert homologation and the HornerWadsworthEmmons reaction. [2] Edwin Vedejs's NMR studies first revealed the importance of oxaphosphetanes in the mechanism of the Wittig reaction in the 1970s. [3] [4]

  6. Triethyl phosphonoacetate - Wikipedia

    en.wikipedia.org/wiki/Triethyl_phosphonoacetate

    Triethyl phosphonoacetate is a reagent for organic synthesis used in the Horner-Wadsworth-Emmons reaction (HWE) or the Horner-Emmons modification. Triethyl phosphonoacetate can be added dropwise to sodium methoxide solution to prepare a phosphonate anion. It has an acidic proton that can easily be abstracted by a weak base.

  7. Elias James Corey - Wikipedia

    en.wikipedia.org/wiki/Elias_James_Corey

    The Wittig reaction affords the cis product, while the Horner-Wadsworth Emmons produces the trans olefin. The published synthesis reveals a 1:1 diastereomeric mixture of the carbonyl reduction using zinc borohydride. However, years later Corey and co-workers established the CBS reduction. One of the examples that exemplified this protocol was ...

  8. List of organic reactions - Wikipedia

    en.wikipedia.org/wiki/List_of_organic_reactions

    Winstein reaction; Wittig reaction; Wittig rearrangement: 1,2-Wittig rearrangement; 2,3-Wittig rearrangement; WittigHorner reaction; Wohl degradation; Wohl–Aue reaction; Wohler synthesis; Wohl–Ziegler reaction; Wolffenstein–Böters reaction; Wolff rearrangement; Wolff–Kishner reduction; Woodward cis-hydroxylation; Woodward–Hoffmann ...

  9. Organophosphorus chemistry - Wikipedia

    en.wikipedia.org/wiki/Organophosphorus_chemistry

    For example, dimethylmethylphosphonate (see figure above) arises from the rearrangement of trimethylphosphite, which is catalyzed by methyl iodide. In the HornerWadsworthEmmons reaction and the Seyferth–Gilbert homologation, phosphonates are used in reactions with carbonyl compounds.