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  2. Epoxide - Wikipedia

    en.wikipedia.org/wiki/Epoxide

    A generic epoxide. In organic chemistry, an epoxide is a cyclic ether, where the ether forms a three-atom ring: two atoms of carbon and one atom of oxygen. This triangular structure has substantial ring strain, making epoxides highly reactive, more so than other ethers. They are produced on a large scale for many applications.

  3. Ring strain - Wikipedia

    en.wikipedia.org/wiki/Ring_strain

    In alkanes, optimum overlap of atomic orbitals is achieved at 109.5°. The most common cyclic compounds have five or six carbons in their ring. [6] Adolf von Baeyer received a Nobel Prize in 1905 for the discovery of the Baeyer strain theory, which was an explanation of the relative stabilities of cyclic molecules in 1885.

  4. Ring-opening metathesis polymerisation - Wikipedia

    en.wikipedia.org/wiki/Ring-opening_metathesis...

    The mechanism of homogeneous ring-opening metathesis polymerization is well-studied. It is similar to any olefin metathesis reaction. Initiation occurs by forming an open coordination site on the catalyst. Propagation happens via a metallacycle intermediate formed after a 2+2 cycloaddition. When using a G3 catalyst, 2+2 cycloaddition is the ...

  5. Ring-opening polymerization - Wikipedia

    en.wikipedia.org/wiki/Ring-opening_polymerization

    In polymer chemistry, ring-opening polymerization (ROP) is a form of chain-growth polymerization in which the terminus of a polymer chain attacks cyclic monomers to form a longer polymer (see figure). The reactive center can be radical, anionic or cationic. Ring-opening of cyclic monomers is often driven by the relief of bond-angle strain.

  6. Johnson–Corey–Chaykovsky reaction - Wikipedia

    en.wikipedia.org/wiki/Johnson–Corey...

    The synthesis of epoxides via this method serves as an important retrosynthetic alternative to the traditional epoxidation reactions of olefins. Johnson–Corey–Chaykovsky Reaction. The reaction is most often employed for epoxidation via methylene transfer, and to this end has been used in several notable total syntheses (See Synthesis of ...

  7. Base-promoted epoxide isomerization - Wikipedia

    en.wikipedia.org/wiki/Base-promoted_epoxide...

    Other processes may take place competitively under basic conditions, particularly when β-elimination is slow or not possible. [6] These pathways likely begin with lithiation of a carbon in the epoxide ring, followed by α-elimination to afford a carbene intermediate. 1,2-hydrogen migration leads to ketones, [2] while intramolecular C–H insertion affords cyclic alcohols with the formation of ...

  8. Ethylene oxide - Wikipedia

    en.wikipedia.org/wiki/Ethylene_oxide

    It is a cyclic ether and the simplest epoxide: a three-membered ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless and flammable gas with a faintly sweet odor. Because it is a strained ring, ethylene oxide easily participates in a number of addition reactions that result in ring-opening.

  9. Kinetic resolution - Wikipedia

    en.wikipedia.org/wiki/Kinetic_resolution

    In 1996, Jacobsen and coworkers developed a methodology for the kinetic resolution of epoxides via nucleophilic ring-opening with attack by an azide anion. The (R,R) catalyst is shown. [ 21 ] The catalyst could effectively, with loadings as low as 0.5 mol%, open the epoxide at the terminal position enantioselectively, yielding enantioenriched ...