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  2. Ketene cycloaddition - Wikipedia

    en.wikipedia.org/wiki/Ketene_cycloaddition

    The progress of the reaction can be estimated by disappearance of the characteristic yellow color of the ketene, by loss of the band at about 2100 cm −1 in the infrared spectrum, or by 1 H NMR spectroscopy. Ketene, monoalkylketenes, and dimethylketene are usually allowed to react at or below room temperature, whereas the higher molecular ...

  3. Inherent chirality - Wikipedia

    en.wikipedia.org/wiki/Inherent_chirality

    Alkenes have no classical chirality, so generally, an external stereogenic center must be introduced. However, by locking the alkene into a conformation through the use of an achiral buckle allows for the creation of an inherently chiral alkene. Inherently chiral alkenes have been synthesized through the use of dialkoxysilanes, with a large ...

  4. Sharpless asymmetric dihydroxylation - Wikipedia

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

    The reaction has been applied to alkenes of virtually every substitution, often high enantioselectivities are realized, with the chiral outcome controlled by the choice of dihydroquinidine (DHQD) vs dihydroquinine (DHQ) as the ligand. Asymmetric dihydroxylation reactions are also highly site selective, providing products derived from reaction ...

  5. Syn and anti addition - Wikipedia

    en.wikipedia.org/wiki/Syn_and_anti_addition

    In organic chemistry, syn-and anti-addition are different ways in which substituent molecules can be added to an alkene (R 2 C=CR 2) or alkyne (RC≡CR).The concepts of syn and anti addition are used to characterize the different reactions of organic chemistry by reflecting the stereochemistry of the products in a reaction.

  6. Dihydroxylation - Wikipedia

    en.wikipedia.org/wiki/Dihydroxylation

    Dihydroxylation is the process by which an alkene is converted into a vicinal diol.Although there are many routes to accomplish this oxidation, the most common and direct processes use a high-oxidation-state transition metal (typically osmium or manganese).

  7. 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 amounts."

  8. Chiral auxiliary - Wikipedia

    en.wikipedia.org/wiki/Chiral_auxiliary

    In stereochemistry, a chiral auxiliary is a stereogenic group or unit that is temporarily incorporated into an organic compound in order to control the stereochemical outcome of the synthesis. [1] [2] The chirality present in the auxiliary can bias the stereoselectivity of one or more subsequent reactions. The auxiliary can then be typically ...

  9. Polymerization - Wikipedia

    en.wikipedia.org/wiki/Polymerization

    [1] [2] [3] There are many forms of polymerization [4] and different systems exist to categorize them. IUPAC definition for polymerization In chemical compounds , polymerization can occur via a variety of reaction mechanisms that vary in complexity due to the functional groups present in the reactants [ 3 ] and their inherent steric effects .