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  2. Alkyl group - Wikipedia

    en.wikipedia.org/wiki/Alkyl_group

    Free alkyls occur as neutral radicals, as anions, or as cations. The cations are called carbocations. The anions are called carbanions. The neutral alkyl free radicals have no special name. Such species are usually encountered only as transient intermediates. However, persistent alkyl radicals with half-lives "from seconds to years" have been ...

  3. Allyl group - Wikipedia

    en.wikipedia.org/wiki/Allyl_group

    Allyl group. In organic chemistry, an allyl group is a substituent with the structural formula −CH2−HC=CH2. It consists of a methylene bridge (−CH2−) attached to a vinyl group (−CH=CH2). [1][2] The name is derived from the scientific name for garlic, Allium sativum. In 1844, Theodor Wertheim isolated an allyl derivative from garlic ...

  4. Ionic liquid - Wikipedia

    en.wikipedia.org/wiki/Ionic_liquid

    From Wikipedia, the free encyclopedia. Salt in the liquid state. The chemical structure of 1-butyl-3-methylimidazolium hexafluorophosphate([BMIM]PF6), a common ionic liquid. Proposed structure of an imidazolium-based ionic liquid. An ionic liquid(IL) is a saltin the liquidstate at ambient conditions.

  5. Cationic polymerization - Wikipedia

    en.wikipedia.org/wiki/Cationic_polymerization

    The association is strongest as a covalent bond and weakest when the pair exists as free ions. [6] In cationic polymerization, the ions tend to be in equilibrium between an ion pair (either tight or solvent-separated) and free ions. [2] The more polar the solvent used in the reaction, the better the solvation and separation of the ions.

  6. Sodium bromide - Wikipedia

    en.wikipedia.org/wiki/Sodium_bromide

    It is a source of the bromide nucleophile to convert alkyl chlorides to more reactive alkyl bromides by the Finkelstein reaction: NaBr + RCl → RBr + NaCl (R = alkyl) Once a large need in photography, but now shrinking, the photosensitive salt silver bromide is prepared using NaBr.

  7. Leaving group - Wikipedia

    en.wikipedia.org/wiki/Leaving_group

    Leaving group. In chemistry, a leaving group is defined by the IUPAC as an atom or group of atoms that detaches from the main or residual part of a substrate during a reaction or elementary step of a reaction. [1] However, in common usage, the term is often limited to a fragment that departs with a pair of electrons in heterolytic bond cleavage ...

  8. List of chemistry mnemonics - Wikipedia

    en.wikipedia.org/wiki/List_of_chemistry_mnemonics

    Cations are positively (+) charged ions while anions are negatively (−) charged. This can be remembered with the help of the following mnemonics. Cats have paws ⇔ Cations are pawsitive. [23] Ca+ion: The letter t in cation looks like a + (plus) sign. [24] An anion is a negative ion. (An egative ionAnion). [25]

  9. Alkylation - Wikipedia

    en.wikipedia.org/wiki/Alkylation

    Alkylation. Alkylation is a chemical reaction that entails transfer of an alkyl group. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). [1] Alkylating agents are reagents for effecting alkylation. Alkyl groups can also be removed in a process known as dealkylation.