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  2. Pyrimidine - Wikipedia

    en.wikipedia.org/wiki/Pyrimidine

    Pyrimidine (C 4 H 4 N 2; / p ɪ ˈ r ɪ. m ɪ ˌ d iː n, p aɪ ˈ r ɪ. m ɪ ˌ d iː n /) is an aromatic, heterocyclic, organic compound similar to pyridine (C 5 H 5 N). [3] One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has nitrogen atoms at positions 1 and 3 in the ring.

  3. Borylation - Wikipedia

    en.wikipedia.org/wiki/Borylation

    Boronic acids and esters are classified depending on the type of carbon group (R) directly bonded to boron, for example alkyl-, alkenyl-, alkynyl-, and aryl-boronic esters. The most common type of starting materials that incorporate boronic esters into organic compounds for transition metal catalyzed borylation reactions have the general ...

  4. Boronic acid - Wikipedia

    en.wikipedia.org/wiki/Boronic_acid

    The general structure of a boronic acid, where R is a substituent. A boronic acid is an organic compound related to boric acid (B(OH) 3) in which one of the three hydroxyl groups (−OH) is replaced by an alkyl or aryl group (represented by R in the general formula R−B(OH) 2). [1]

  5. Boron compounds - Wikipedia

    en.wikipedia.org/wiki/Boron_compounds

    Ball-and-stick model of superconductor magnesium diboride. Boron atoms lie in hexagonal aromatic graphite-like layers, with a charge of −1 on each boron atom. Magnesium(II) ions lie between layers. Binary metal-boron compounds, the metal borides, contain boron in negative oxidation states. Illustrative is magnesium diboride (MgB 2). Each ...

  6. Borinic acid - Wikipedia

    en.wikipedia.org/wiki/Borinic_acid

    Borinic acid, also known as boronous acid, is an oxyacid of boron with formula H 2 BOH. Borinate is the associated anion of borinic acid with formula H 2 BO −; however, being a Lewis acid, the form in basic solution is H 2 B(OH) − 2. Borinic acid can be formed as the first step in the hydrolysis of diborane: [1] BH 3 + H 2 O → H 2 BOH + H ...

  7. Tetrahydroxydiboron - Wikipedia

    en.wikipedia.org/wiki/Tetrahydroxydiboron

    The reaction of boron trichloride with alcohols was reported in 1931, and was used to prepare dimethoxyboron chloride, B(OCH 3) 2 Cl. [3] Egon Wiberg and Wilhelm Ruschmann used it to prepare tetrahydroxydiboron by first introducing the boron–boron bond by reduction with sodium and then hydrolysing the resulting tetramethoxydiboron, B 2 (OCH 3) 4, to produce what they termed sub-boric acid. [4]

  8. Polyhedral skeletal electron pair theory - Wikipedia

    en.wikipedia.org/wiki/Polyhedral_skeletal...

    Electron count: 5 × B + 5 × H + 4 (for the negative charge) = 5 × 3 + 5 × 1 + 4 = 24 Since n = 5, 4n + 4 = 24, so the cluster is nido. Starting from an octahedron, one of the vertices is removed. The rules are useful in also predicting the structure of carboranes. Example: C 2 B 7 H 13

  9. Organoboron chemistry - Wikipedia

    en.wikipedia.org/wiki/Organoboron_chemistry

    Structure of a rare monomeric boron hydride, R = i-Pr. [4] The most-studied class of organoboron compounds has the formula BR n H 3−n. These compounds are catalysts, reagents, and synthetic intermediates. The trialkyl and triaryl derivatives feature a trigonal-planar boron center that is typically only weakly Lewis acidic.