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  2. Neighbouring group participation - Wikipedia

    en.wikipedia.org/wiki/Neighbouring_group...

    In organic chemistry, neighbouring group participation (NGP, also known as anchimeric assistance) has been defined by the International Union of Pure and Applied Chemistry (IUPAC) as the interaction of a reaction centre with a lone pair of electrons in an atom or the electrons present in a sigma or pi bond contained within the parent molecule but not conjugated with the reaction centre.

  3. Cieplak effect - Wikipedia

    en.wikipedia.org/wiki/Cieplak_Effect

    The Cieplak effect relies on the stabilizing interaction of mixing full and empty orbitals to delocalize electrons, known as hyperconjugation. [2] When the highest occupied molecular orbital of one system and the lowest unoccupied molecular orbital of another system have comparable energies and spatial overlap, the electrons can delocalize and sink into a lower energy level.

  4. Aluminium(I) nucleophiles - Wikipedia

    en.wikipedia.org/wiki/Aluminium(I)_nucleophiles

    The first isolation of a nucleophilic aluminium center was achieved in 2018 by Aldridge, Goicoechea and coworkers when they were able to synthesize the first aluminyl anion, [5] following the discoveries of gallium [6] [7] [8] and indium [9] analogues, heavier group 13 analogues which are more stable than aluminium in the lower +1 oxidation ...

  5. Nucleophile - Wikipedia

    en.wikipedia.org/wiki/Nucleophile

    In chemistry, a nucleophile is a chemical species that forms bonds by donating an electron pair. All molecules and ions with a free pair of electrons or at least one pi bond can act as nucleophiles. Because nucleophiles donate electrons, they are Lewis bases. Nucleophilic describes the affinity of a nucleophile to bond with positively charged ...

  6. Electron configurations of the elements (data page) - Wikipedia

    en.wikipedia.org/wiki/Electron_configurations_of...

    However there are numerous exceptions; for example the lightest exception is chromium, which would be predicted to have the configuration 1s 2 2s 2 2p 6 3s 2 3p 6 3d 4 4s 2, written as [Ar] 3d 4 4s 2, but whose actual configuration given in the table below is [Ar] 3d 5 4s 1. Note that these electron configurations are given for neutral atoms in ...

  7. Template:Periodic table (electron configuration) - Wikipedia

    en.wikipedia.org/wiki/Template:Periodic_table...

    4 9 F 2 5 10 Ne 2 6 [Ne] 3s: 3p: 11 Na 1 - 12 Mg 2 - 13 Al 2 1 14 Si 2 2 15 P 2 3 16 S 2 4 17 Cl 2 5 18 Ar 2 6 [Ar] 4s: 3d: 4p: 19 K 1-- 20 Ca 2-- 21 Sc 2 1 - 22 Ti 2 2 - 23 V 2 3 - 24 Cr 1 5 - 25 Mn 2 5 - 26 Fe 2 6 - 27 Co 2 7 - 28 Ni 2 8 - 29 Cu 1 10 - 30 Zn 2 10 - 31 Ga 2 10 1 32 Ge 2 10 2 33 As 2 10 3 34 Se 2 10 4 35 Br 2 10 5 36 Kr 2 10 6 ...

  8. Nucleophilic substitution - Wikipedia

    en.wikipedia.org/wiki/Nucleophilic_substitution

    In chemistry, a nucleophilic substitution (S N) is a class of chemical reactions in which an electron-rich chemical species (known as a nucleophile) replaces a functional group within another electron-deficient molecule (known as the electrophile). The molecule that contains the electrophile and the leaving functional group is called the substrate.

  9. Template:Reaction mechanisms - Wikipedia

    en.wikipedia.org/wiki/Template:Reaction_mechanisms

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