When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Lewis acids and bases - Wikipedia

    en.wikipedia.org/wiki/Lewis_acids_and_bases

    A Lewis base is an atomic or molecular species where the highest occupied molecular orbital (HOMO) is highly localized. Typical Lewis bases are conventional amines such as ammonia and alkyl amines. Other common Lewis bases include pyridine and its derivatives. Some of the main classes of Lewis bases are

  3. Benzene - Wikipedia

    en.wikipedia.org/wiki/Benzene

    Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Benzene is a colorless and highly flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline.

  4. Ligand - Wikipedia

    en.wikipedia.org/wiki/Ligand

    In coordination chemistry, a ligand [a] is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs , often through Lewis bases . [ 1 ]

  5. Benzyl group - Wikipedia

    en.wikipedia.org/wiki/Benzyl_group

    Benzyl group and derivatives: Benzyl group, benzyl radical, benzyl amine, benzyl bromide, benzyl chloroformate, and benzyl methyl ether. R = heteroatom, alkyl, aryl, allyl etc. or other substituents. In organic chemistry, benzyl is the substituent or molecular fragment possessing the structure R−CH 2 −C 6 H 5.

  6. Electron counting - Wikipedia

    en.wikipedia.org/wiki/Electron_counting

    Many rules in chemistry rely on electron-counting: Octet rule is used with Lewis structures for main group elements, especially the lighter ones such as carbon, nitrogen, and oxygen, 18-electron rule [2] in inorganic chemistry and organometallic chemistry of transition metals, Hückel's rule for the π-electrons of aromatic compounds,

  7. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    A simple Lewis model also does not account for the phenomenon of aromaticity. For instance, Lewis structures do not offer an explanation for why cyclic C 6 H 6 (benzene) experiences special stabilization beyond normal delocalization effects, while C 4 H 4 (cyclobutadiene) actually experiences a special destabilization.

  8. Parent structure - Wikipedia

    en.wikipedia.org/wiki/Parent_structure

    In chemistry, a parent structure is the structure of an unadorned ion or molecule from which derivatives can be visualized. [1] Parent structures underpin systematic nomenclature and facilitate classification. Fundamental parent structures have one or no functional groups and often have various types of symmetry.

  9. Lewis acid catalysis - Wikipedia

    en.wikipedia.org/wiki/Lewis_Acid_Catalysis

    Common Lewis acid catalysts are based on main group metals such as aluminum, boron, silicon, and tin, as well as many early (titanium, zirconium) and late (iron, copper, zinc) d-block metals. The metal atom forms an adduct with a lone-pair bearing electronegative atom in the substrate, such as oxygen (both sp 2 or sp 3), nitrogen, sulfur, and ...