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  2. Hammett equation - Wikipedia

    en.wikipedia.org/wiki/Hammett_equation

    Consider para-disubstituted benzene p-F-C 6 H 4-Z, where Z is a substituent such as NH 2, NO 2, etc. The fluorine atom is para with respect to the substituent Z in the benzene ring. The image on the right shows four distinguished ring carbon atoms, C1, C2, C3, C4 in p-F-C 6 H 4-Z molecule. The carbon with Z is defined as C1(ipso) and ...

  3. Electrophilic aromatic directing groups - Wikipedia

    en.wikipedia.org/wiki/Electrophilic_aromatic...

    Structure Type of electronic effect Directing effect Strong trifluoromethylsulfonyl group [13]-SO 2 CF 3 –I, –M meta (substituted) ammonium groups [14]-NR 3 + (R = alkyl or H) –I nitro group-NO 2 –I, –M sulfonic acids and sulfonyl groups-SO 3 H, -SO 2 R cyano group-C≡N trihalomethyl groups (strongest for -CF 3 group) -CX 3 (X = F ...

  4. Nucleophilic aromatic substitution - Wikipedia

    en.wikipedia.org/wiki/Nucleophilic_aromatic...

    The mechanism of S N 2 reaction does not occur due to steric hindrance of the benzene ring. In order to attack the C atom, the nucleophile must approach in line with the C-LG (leaving group) bond from the back, where the benzene ring lies. It follows the general rule for which S N 2 reactions occur only at a tetrahedral carbon atom.

  5. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    Lewis structures – also called Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDs) – are diagrams that show the bonding between atoms of a molecule, as well as the lone pairs of electrons that may exist in the molecule. [1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The ...

  6. Electrophilic aromatic substitution - Wikipedia

    en.wikipedia.org/wiki/Electrophilic_aromatic...

    The most widely practised example of this reaction is the ethylation of benzene. Approximately 24,700,000 tons were produced in 1999. [2] (After dehydrogenation and polymerization, the commodity plastic polystyrene is produced.) In this process, acids are used as catalyst to generate the incipient carbocation. Many other electrophilic reactions ...

  7. Béchamp reduction - Wikipedia

    en.wikipedia.org/wiki/Béchamp_reduction

    The Béchamp reduction (or Béchamp process) is a chemical reaction that converts aromatic nitro compounds to their corresponding anilines using iron as the reductant: [1] 4 C 6 H 5 NO 2 + 9 Fe + 4 H 2 O → 4 C 6 H 5 NH 2 + 3 Fe 3 O 4. This reaction was once a major route to aniline, but catalytic hydrogenation is the preferred method. [2]

  8. Nitro compound - Wikipedia

    en.wikipedia.org/wiki/Nitro_compound

    The structure of an organic nitro compound. In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups (−NO 2). The nitro group is one of the most common explosophores (functional group that makes a compound explosive) used globally. The nitro group is also strongly electron-withdrawing.

  9. Structural formula - Wikipedia

    en.wikipedia.org/wiki/Structural_formula

    Skeletal structural formula of Vitamin B 12.Many organic molecules are too complicated to be specified by a molecular formula.. The structural formula of a chemical compound is a graphic representation of the molecular structure (determined by structural chemistry methods), showing how the atoms are connected to one another. [1]