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  2. Selenoxide elimination - Wikipedia

    en.wikipedia.org/wiki/Selenoxide_elimination

    α-Selanylation of carbonyl compounds can be accomplished with electrophilic or nucleophilic selanylating reagents. Usually, simple phenylseleno compounds are used in elimination reactions; although 2-nitrophenylselenides react more quickly, they are more expensive to prepare, and phenylselenides typically react in minutes.

  3. Stereochemistry - Wikipedia

    en.wikipedia.org/wiki/Stereochemistry

    Stereochemistry, a subdiscipline of chemistry, studies the spatial arrangement of atoms that form the structure of molecules and their manipulation. [1] The study of stereochemistry focuses on the relationships between stereoisomers, which are defined as having the same molecular formula and sequence of bonded atoms (constitution) but differing in the geometric positioning of the atoms in space.

  4. Reductive elimination - Wikipedia

    en.wikipedia.org/wiki/Reductive_elimination

    The prominent mechanism is a concerted pathway, meaning that it is a nonpolar, three-centered transition state with retention of stereochemistry. In addition, an S N 2 mechanism, which proceeds with inversion of stereochemistry, or a radical mechanism, which proceeds with obliteration of stereochemistry, are other possible pathways for ...

  5. Demjanov rearrangement - Wikipedia

    en.wikipedia.org/wiki/Demjanov_rearrangement

    The Demjanov rearrangement is a method to produce a 1-carbon ring enlargement in four, five or six membered rings. The resulting five, six, and seven-membered rings can then be used in further synthetic reactions.

  6. Dynamic stereochemistry - Wikipedia

    en.wikipedia.org/wiki/Dynamic_stereochemistry

    In chemistry, dynamic stereochemistry studies the effect of stereochemistry on the reaction rate of a chemical reaction. Stereochemistry is involved in: stereospecific reactions; stereoselective or asymmetric reactions; racemisation processes

  7. Stereoselectivity - Wikipedia

    en.wikipedia.org/wiki/Stereoselectivity

    An example of modest stereoselectivity is the dehydrohalogenation of 2-iodobutane which yields 60% trans-2-butene and 20% cis-2-butene. [5] Since alkene geometric isomers are also classified as diastereomers, this reaction would also be called diastereoselective.

  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. Atropisomer - Wikipedia

    en.wikipedia.org/wiki/Atropisomer

    Determining stereochemistry in atropisomers using the helicity rule follows the priority: front substituent A > backward substituent A > front substituent B > backward substituent B Determining the axial stereochemistry of biaryl atropisomers can be accomplished through the use of a Newman projection along the axis of hindered rotation.