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  2. Boron tribromide - Wikipedia

    en.wikipedia.org/wiki/Boron_tribromide

    Boron tribromide is commercially available and is a strong Lewis acid.. It is an excellent demethylating or dealkylating agent for the cleavage of ethers, also with subsequent cyclization, often in the production of pharmaceuticals.

  3. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    [1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The Atom and the Molecule, a Lewis structure can be drawn for any covalently bonded molecule, as well as coordination compounds. [4] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.

  4. Boron compounds - Wikipedia

    en.wikipedia.org/wiki/Boron_compounds

    The trihalides adopt a planar trigonal structure. These compounds are Lewis acids in that they readily form adducts with electron-pair donors, which are called Lewis bases. For example, fluoride (F −) and boron trifluoride (BF 3) combined to give the tetrafluoroborate anion, BF 4 −. Boron trifluoride is used in the petrochemical industry as ...

  5. Boron triiodide - Wikipedia

    en.wikipedia.org/wiki/Boron_triiodide

    In its pure state, boron triiodide forms colorless, otherwise reddish, shiny, air and hydrolysis-sensitive [3] crystals, which have a hexagonal crystal structure (a = 699.09 ± 0.02 pm, c = 736.42 ± 0.03 pm, space group P6 3 /m (space group no. 176)). [4] Boron triiodide is a strong Lewis acid and soluble in carbon disulfide. [2]

  6. Boron trifluoride - Wikipedia

    en.wikipedia.org/wiki/Boron_trifluoride

    Such measurements have revealed the following sequence for the Lewis acidity: BF 3 < BCl 3 < BBr 3 < BI 3 (strongest Lewis acid) This trend is commonly attributed to the degree of π-bonding in the planar boron trihalide that would be lost upon pyramidalization of the BX 3 molecule. [17] which follows this trend: BF 3 > BCl 3 > BBr 3 < BI 3 ...

  7. 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

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  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 possibly arranged in the real three-dimensional space.