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  2. Template reaction - Wikipedia

    en.wikipedia.org/wiki/Template_reaction

    The template effects emphasizes the pre-organization provided by the coordination sphere, although the coordination modifies the electronic properties (acidity, electrophilicity, etc.) of ligands. [1] An early example is the dialkylation of a nickel dithiolate: [2] The corresponding alkylation in the absence of a metal ion would yield polymers.

  3. Aza-Cope rearrangement - Wikipedia

    en.wikipedia.org/wiki/Aza-Cope_rearrangement

    The aza-Cope rearrangements are predicted by the Woodward-Hoffman rules to proceed suprafacially. However, while never explicitly studied, Overman and coworkers have hypothesized that, as with the base-catalyzed oxy-Cope rearrangement, the charged atom distorts the sigmatropic rearrangement from a purely concerted reaction mechanism (as expected in the Cope rearrangement), to one with partial ...

  4. Zintl phase - Wikipedia

    en.wikipedia.org/wiki/Zintl_phase

    Many examples similarly exist for heteroatomic clusters where the polyanion is composed of greater than one main group element. Some examples are listed below. Some examples are listed below. [ 15 ] [ 16 ] Zintl ions are also capable of reacting with ligands and transition metals, and further 'heteroatomic examples are discussed below ...

  5. Bromate - Wikipedia

    en.wikipedia.org/wiki/Bromate

    The bromate anion, BrO − 3, is a bromine-based oxoanion. A bromate is a chemical compound that contains this ion. Examples of bromates include sodium bromate (NaBrO 3) and potassium bromate (KBrO 3). Bromates are formed many different ways in municipal drinking water. The most common is the reaction of ozone and bromide: Br − + O 3 → BrO ...

  6. Hypobromite - Wikipedia

    en.wikipedia.org/wiki/Hypobromite

    The hypobromite ion, also called alkaline bromine water, is BrO −. Bromine is in the +1 oxidation state. The Br–O bond length is 1.82 Å. [1] Hypobromite is the bromine compound analogous to hypochlorites found in common bleaches, and in immune cells. In many ways, hypobromite functions in the same manner as hypochlorite, and is also used ...

  7. Boranylium ions - Wikipedia

    en.wikipedia.org/wiki/Boranylium_ions

    Various representations of bonding in borenium ions. [2]A borenium ion is an inorganic cation with the chemical formula [BR 2 L] +In this class of molecules, the electron-deficient boron center has two valence electrons involved in sigma bonding with two ligands, while the third ligand is a two-electron donor such that the overall charge of the complex is +1. [1]

  8. Covalent radius - Wikipedia

    en.wikipedia.org/wiki/Covalent_radius

    For heteroatomic A–B bonds, ionic terms may enter. Often the polar covalent bonds are shorter than would be expected based on the sum of covalent radii. Tabulated values of covalent radii are either average or idealized values, which nevertheless show a certain transferability between different situations, which makes them useful.

  9. Born–Haber cycle - Wikipedia

    en.wikipedia.org/wiki/Born–Haber_cycle

    Born–Haber cycles are used primarily as a means of calculating lattice energy (or more precisely enthalpy [note 1]), which cannot otherwise be measured directly. The lattice enthalpy is the enthalpy change involved in the formation of an ionic compound from gaseous ions (an exothermic process ), or sometimes defined as the energy to break the ...