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  2. Hückel's rule - Wikipedia

    en.wikipedia.org/wiki/Hückel's_rule

    Hückel's rule can also be applied to molecules containing other atoms such as nitrogen or oxygen. For example pyridine (C 5 H 5 N) has a ring structure similar to benzene, except that one -CH- group is replaced by a nitrogen atom with no hydrogen. There are still six π electrons and the pyridine molecule is also aromatic and known for its ...

  3. File:Benzene phase diagram.svg - Wikipedia

    en.wikipedia.org/wiki/File:Benzene_phase_diagram.svg

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  4. Aromatic compound - Wikipedia

    en.wikipedia.org/wiki/Aromatic_compound

    Heteroarenes are aromatic compounds, where at least one methine or vinylene (-C= or -CH=CH-) group is replaced by a heteroatom: oxygen, nitrogen, or sulfur. [3] Examples of non-benzene compounds with aromatic properties are furan, a heterocyclic compound with a five-membered ring that includes a single oxygen atom, and pyridine, a heterocyclic compound with a six-membered ring containing one ...

  5. File:Benzene Structural diagram.svg - Wikipedia

    en.wikipedia.org/wiki/File:Benzene_Structural...

    The following other wikis use this file: Usage on de.wikibooks.org Organische Chemie für Schüler/ Aromatische Kohlenwasserstoffe; Organische Chemie für Schüler/ Druckversion

  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. Electrophilic aromatic directing groups - Wikipedia

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

    Diagram showing the ortho, meta and para positions relative to a substituent X on a benzene ring. Electron donating groups are typically divided into three levels of activating ability (The "extreme" category can be seen as "strong".) Electron withdrawing groups are assigned to similar groupings.

  8. Arene substitution pattern - Wikipedia

    en.wikipedia.org/wiki/Arene_substitution_pattern

    In meta-substitution the substituents occupy positions 1 and 3 (corresponding to R and meta in the diagram). In para-substitution, the substituents occupy the opposite ends (positions 1 and 4, corresponding to R and para in the diagram). The toluidines serve as an example for these three types of substitution.

  9. Heterocyclic compound - Wikipedia

    en.wikipedia.org/wiki/Heterocyclic_compound

    A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). [1] Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of organic heterocycles .