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  • alkene
  • Hydrogenation typically constitutes the addition of pairs of hydrogen atoms to a molecule, generally an alkene. (primidi.com)
  • An important characteristic of alkene and alkyne hydrogenations, both the homogeneously and heterogeneously catalyzed versions, is that hydrogen addition occurs with "syn addition", with hydrogen entering from the least hindered side. (wikipedia.org)
  • Asymmetric hydrogenation is a chemical reaction that adds two atoms of hydrogen preferentially to one of two faces of an unsaturated substrate molecule, such as an alkene or ketone. (wikipedia.org)
  • The combination of magnesium and methanol is used in alkene reductions, e.g. the synthesis of asenapine: Organocatalytic transfer hydrogenation has been described by the group of List in 2004 in a system with a Hantzsch ester as hydride donor and an amine catalyst: In this particular reaction the substrate is an α,β-unsaturated carbonyl compound. (wikipedia.org)
  • isomerization
  • In food production, liquid cis-unsaturated fats such as vegetable oils are hydrogenated to produce saturated fats, which have more desirable physical properties, e.g. they melt at a desirable temperature (30-40 °C). Partial hydrogenation of the unsaturated fat converts some of the cis double bonds into trans double bonds by an isomerization reaction with the catalyst used for the hydrogenation, which yields a trans fat. (wikipedia.org)
  • Besides hydrogenation, the catalyst catalyzes the isomerization and hydroboration of alkenes. (wikipedia.org)
  • molecule
  • Preferential hydrogenation of one functional group in a molecule over another is the chemoselective process, while regioselective hydrogenation is the preferential formation of one constitutional isomer of the product in a reaction in which other isomers may also be formed, and the stereoselective hydrogenation is the formation of an excess of one stereoisomer over others. (springer.com)
  • While distinguishing between the two mechanisms is difficult, the difference between the two for asymmetric hydrogenation is relatively unimportant since both converge to a common intermediate before any stereochemical information is transferred to the product molecule. (wikipedia.org)