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  2. Markovnikov's rule - Wikipedia

    en.wikipedia.org/wiki/Markovnikov's_rule

    The rule states that with the addition of a protic acid HX or other polar reagent to an asymmetric alkene, the acid hydrogen (H) or electropositive part gets attached to the carbon with more hydrogen substituents, and the halide (X) group or electronegative part gets attached to the carbon with more alkyl substituents. This is in contrast to ...

  3. Shi epoxidation - Wikipedia

    en.wikipedia.org/wiki/Shi_epoxidation

    The Shi epoxidation is a chemical reaction described as the asymmetric epoxidation of alkenes with oxone (potassium peroxymonosulfate) and a fructose-derived catalyst (1). This reaction is thought to proceed via a dioxirane intermediate, generated from the catalyst ketone by oxone (potassium peroxymonosulfate).

  4. Enantioselective synthesis - Wikipedia

    en.wikipedia.org/wiki/Enantioselective_synthesis

    Enantioselective synthesis, also called asymmetric synthesis, [1] is a form of chemical synthesis. It is defined by IUPAC as "a chemical reaction (or reaction sequence) in which one or more new elements of chirality are formed in a substrate molecule and which produces the stereoisomeric ( enantiomeric or diastereomeric ) products in unequal ...

  5. Sharpless asymmetric dihydroxylation - Wikipedia

    en.wikipedia.org/wiki/Sharpless_asymmetric_di...

    K. Barry Sharpless was the first to develop a general, reliable enantioselective alkene dihydroxylation, referred to as the Sharpless asymmetric dihydroxylation (SAD). Low levels of OsO 4 are combined with a stoichiometric ferricyanide oxidant in the presence of chiral nitrogenous ligands to create an asymmetric environment around the oxidant.

  6. Jacobsen's catalyst - Wikipedia

    en.wikipedia.org/wiki/Jacobsen's_catalyst

    It is used as an asymmetric catalyst in the Jacobsen epoxidation, which is renowned for its ability to enantioselectively transform prochiral alkenes into epoxides. [ 1 ] [ 2 ] Before its development, catalysts for the asymmetric epoxidation of alkenes required the substrate to have a directing functional group, such as an alcohol as seen in ...

  7. ZACA reaction - Wikipedia

    en.wikipedia.org/wiki/ZACA_reaction

    The zirconium-catalyzed asymmetric carbo-alumination reaction (or ZACA reaction) was developed by Nobel laureate Ei-ichi Negishi. [1] It facilitates the chiral functionalization of alkenes using organoaluminium compounds under the influence of chiral bis-indenylzirconium catalysts (e.g. bearing chiral terpene residues, [2] as in (+)- or (−)-bis[(1-neomenthyl)indenyl]zirconium dichloride [3 ...

  8. Alkene - Wikipedia

    en.wikipedia.org/wiki/Alkene

    Alkenes are generally colorless non-polar compounds, somewhat similar to alkanes but more reactive. The first few members of the series are gases or liquids at room temperature. The simplest alkene, ethylene (C 2 H 4) (or "ethene" in the IUPAC nomenclature) is the organic compound produced on the largest scale industrially. [5]

  9. Jacobsen epoxidation - Wikipedia

    en.wikipedia.org/wiki/Jacobsen_epoxidation

    Jacobsen's catalysts R = Alkyl, O-alkyl, O-trialkyl Best Jacobsen catalyst: R = t Bu Katsuki's catalysts R 1 = Aryl, substituted aryl R 2 = Aryl, Alkyl. The Jacobsen epoxidation, sometimes also referred to as Jacobsen-Katsuki epoxidation is a chemical reaction which allows enantioselective epoxidation of unfunctionalized alkyl- and aryl- substituted alkenes.