Tetrahydroxydiboron

Last updated
Tetrahydroxydiboron
Tetrahydroxydiboron structure.svg
Names
IUPAC name
Hypoboric acid [1]
Other names
(Dihydroxyboranyl)boronic acid
Hypoboric acid
Hypodiboric acid
Sub-boric acid (Unterborsäure in German)
1,1,2,2-Tetrahydroxydiborane
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.222.662 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
UNII
  • InChI=1S/B2H4O4/c3-1(4)2(5)6/h3-6H
    Key: SKOWZLGOFVSKLB-UHFFFAOYSA-N
  • B(B(O)O)(O)O
Properties
B2H4O4
Molar mass 89.65 g·mol−1
AppearanceWhite powder
Density 1.657
very soluble
Solubility ethanol, DMF, DMSO, DMA
Structure
monoclinic P21/c
Thermochemistry
Std molar
entropy
(S298)
125.46 J K1 mol1
1410.43 kJ mol1
Hazards
GHS labelling:
H302, H315, H319, H332, H335
P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P312, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P337+P313, P362, P403+P233, P405, P501
Related compounds
Related compounds
Diborane
Diboron tetrafluoride
Bis(pinacolato)diboron
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Tetrahydroxydiboron is a chemical reagent which can be used to prepare boronic acids. [2]

Contents

Synthesis

The reaction of boron trichloride with alcohols was reported in 1931, and was used to prepare dimethoxyboron chloride, B(OCH3)2Cl. [3] Egon Wiberg and Wilhelm Ruschmann used it to prepare tetrahydroxydiboron by first introducing the boronboron bond by reduction with sodium and then hydrolysing the resulting tetramethoxydiboron, B2(OCH3)4, to produce what they termed sub-boric acid. [4] The methanol used in this process can be recycled:

BCl3   B(OCH3)2Cl    B2(OCH3)4   B2(OH)4

Overall: 2  BCl3  + 2  Na  + 4  H2O   B2(OH)4 + 2  NaCl  + 4  HCl

Reactions

When heated to over 90 °C, tetrahydroxydiboron dehydrates to a polymeric boron(II) oxide. The temperature must rise to 220 °C to be totally free from water. [5]

Tetrahydroxydiboron is a reducing agent. A water solution slowly gives off hydrogen gas. [4]

Related Research Articles

<span class="mw-page-title-main">Acid–base reaction</span> Chemical reaction between an acid and a base

In chemistry, an acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.

A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and chemical formulas. The reactant entities are given on the left-hand side and the product entities are on the right-hand side with a plus sign between the entities in both the reactants and the products, and an arrow that points towards the products to show the direction of the reaction. The chemical formulas may be symbolic, structural, or intermixed. The coefficients next to the symbols and formulas of entities are the absolute values of the stoichiometric numbers. The first chemical equation was diagrammed by Jean Beguin in 1615.

In organic chemistry, an acyl chloride is an organic compound with the functional group −C(=O)Cl. Their formula is usually written R−COCl, where R is a side chain. They are reactive derivatives of carboxylic acids. A specific example of an acyl chloride is acetyl chloride, CH3COCl. Acyl chlorides are the most important subset of acyl halides.

<span class="mw-page-title-main">Hypochlorite</span> An anion

In chemistry, hypochlorite, or chloroxide is an anion with the chemical formula ClO. It combines with a number of cations to form hypochlorite salts. Common examples include sodium hypochlorite and calcium hypochlorite. The Cl-O distance in ClO is 1.69 Å.

Tin(IV) chloride, also known as tin tetrachloride or stannic chloride, is an inorganic compound of tin and chlorine with the formula SnCl4. It is a colorless hygroscopic liquid, which fumes on contact with air. It is used as a precursor to other tin compounds. It was first discovered by Andreas Libavius (1550–1616) and was known as spiritus fumans libavii.

<span class="mw-page-title-main">Sulfonic acid</span> Organic compounds with the structure R−S(=O)2−OH

In organic chemistry, sulfonic acid refers to a member of the class of organosulfur compounds with the general formula R−S(=O)2−OH, where R is an organic alkyl or aryl group and the S(=O)2(OH) group a sulfonyl hydroxide. As a substituent, it is known as a sulfo group. A sulfonic acid can be thought of as sulfuric acid with one hydroxyl group replaced by an organic substituent. The parent compound is the parent sulfonic acid, HS(=O)2(OH), a tautomer of sulfurous acid, S(=O)(OH)2. Salts or esters of sulfonic acids are called sulfonates.

Boron trifluoride is the inorganic compound with the formula BF3. This pungent, colourless, and toxic gas forms white fumes in moist air. It is a useful Lewis acid and a versatile building block for other boron compounds.

<span class="mw-page-title-main">Phosphorus trichloride</span> Chemical compound

Phosphorus trichloride is an inorganic compound with the chemical formula PCl3. A colorless liquid when pure, it is an important industrial chemical, being used for the manufacture of phosphites and other organophosphorus compounds. It is toxic and reacts readily with water to release hydrogen chloride.

<span class="mw-page-title-main">Gold(III) chloride</span> Chemical compound

Gold(III) chloride, traditionally called auric chloride, is an inorganic compound of gold and chlorine with the molecular formula Au2Cl6. The "III" in the name indicates that the gold has an oxidation state of +3, typical for many gold compounds. It has two forms, the monohydrate (AuCl3·H2O) and the anhydrous form, which are both hygroscopic and light-sensitive solids. This compound is a dimer of AuCl3. This compound has a few uses, such as an oxidizing agent and for catalyzing various organic reactions.

<span class="mw-page-title-main">Trimethyl borate</span> Chemical compound

Trimethyl borate is the organoboron compound with the formula B(OCH3)3 and a metal alkoxide. It is a colourless liquid that burns with a green flame. It is an intermediate in the preparation of sodium borohydride and is a popular reagent in organic chemistry. It is a weak Lewis acid (AN = 23, Gutmann-Beckett method).

<span class="mw-page-title-main">Trimethylsilyl chloride</span> Organosilicon compound with the formula (CH3)3SiCl

Trimethylsilyl chloride, also known as chlorotrimethylsilane is an organosilicon compound, with the formula (CH3)3SiCl, often abbreviated Me3SiCl or TMSCl. It is a colourless volatile liquid that is stable in the absence of water. It is widely used in organic chemistry.

Boron trichloride is the inorganic compound with the formula BCl3. This colorless gas is a reagent in organic synthesis. It is highly reactive towards water.

<span class="mw-page-title-main">Triflic acid</span> Chemical compound

Triflic acid, the short name for trifluoromethanesulfonic acid, TFMS, TFSA, HOTf or TfOH, is a sulfonic acid with the chemical formula CF3SO3H. It is one of the strongest known acids. Triflic acid is mainly used in research as a catalyst for esterification. It is a hygroscopic, colorless, slightly viscous liquid and is soluble in polar solvents.

<span class="mw-page-title-main">Chromium(II) chloride</span> Chemical compound

Chromium(II) chloride describes inorganic compounds with the formula CrCl2(H2O)n. The anhydrous solid is white when pure, however commercial samples are often grey or green; it is hygroscopic and readily dissolves in water to give bright blue air-sensitive solutions of the tetrahydrate Cr(H2O)4Cl2. Chromium(II) chloride has no commercial uses but is used on a laboratory-scale for the synthesis of other chromium complexes.

<span class="mw-page-title-main">Chlorosulfuric acid</span> Chemical compound

Chlorosulfuric acid (IUPAC name: sulfurochloridic acid) is the inorganic compound with the formula HSO3Cl. It is also known as chlorosulfonic acid, being the sulfonic acid of chlorine. It is a distillable, colorless liquid which is hygroscopic and a powerful lachrymator. Commercial samples usually are pale brown or straw colored.

<span class="mw-page-title-main">Ortho ester</span> Chemical group with the structure RC(OR)3

In organic chemistry, an ortho ester is a functional group containing three alkoxy groups attached to one carbon atom, i.e. with the general formula RC(OR<span class="nowrap" style="paddingleft:0.05em;">′)3. Orthoesters may be considered as products of exhaustive alkylation of unstable orthocarboxylic acids and it is from these that the name 'ortho ester' is derived. An example is ethyl orthoacetate, CH3C(OCH2CH3)3, more correctly known as 1,1,1-triethoxyethane.

In inorganic chemistry, sulfonyl halide groups occur when a sulfonyl functional group is singly bonded to a halogen atom. They have the general formula RSO2X, where X is a halogen. The stability of sulfonyl halides decreases in the order fluorides > chlorides > bromides > iodides, all four types being well known. The sulfonyl chlorides and fluorides are of dominant importance in this series.

Dimethyldichlorosilane is a tetrahedral organosilicon compound with the formula Si(CH3)2Cl2. At room temperature it is a colorless liquid that readily reacts with water to form both linear and cyclic Si-O chains. Dimethyldichlorosilane is made on an industrial scale as the principal precursor to dimethylsilicone and polysilane compounds.

<span class="mw-page-title-main">Methyltrichlorosilane</span> Chemical compound

Methyltrichlorosilane, also known as trichloromethylsilane, is a monomer and organosilicon compound with the formula CH3SiCl3. It is a colorless liquid with a sharp odor similar to that of hydrochloric acid. As methyltrichlorosilane is a reactive compound, it is mainly used a precursor for forming various cross-linked siloxane polymers.

<span class="mw-page-title-main">Borate esters</span> Organic compounds of the form B(OR)₃ or B₃O₃(OR)₃

In organic chemistry, borate esters are organoboron compounds which are conveniently prepared by the stoichiometric condensation reaction of boric acid with alcohols. There are two main classes of borate esters: orthoborates, B(OR)3 and metaborates, B3O3(OR)3. Metaborates contain 6-membered boroxine rings.

References

  1. "Hypodiboric acid". IUPAC.
  2. Little, Sarah; Trice, Jane (2001). "Tetrahydroxydiboron". Encyclopedia of Reagents for Organic Synthesis . John Wiley & Sons. doi:10.1002/047084289x.rn01181. ISBN   9780470842898.
  3. Wiberg, Egon; Sütterlin, Walther (1931). "Zur Kenntnis einiger Verbindungen vom Typus BCl3−n(OR)n. (Über alkoxyl-substituierte Borchloride)" [Notes on some compounds of type BCl3−n(OR)n. (Via alkoxy-substituted boron chlorides)]. Z. anorg. allg. Chem. (in German). 202 (1): 1–21. doi:10.1002/zaac.19312020102.
  4. 1 2 Wiberg, Egon; Ruschmann, Wilhelm (1937). "Über eine neue Borsäure ('Unterborsäure'︁) der Formel H4B2O4 und ihre Ester" [On a new boric acid ('Sub-boric acid') of the formula H4B2O4 and its esters]. Ber. Dtsch. Chem. Ges. A/B (in German). 70 (6): 1393–1402. doi:10.1002/cber.19370700636.
  5. Wartik, Thomas; Apple, Eugene F. (1955). "A New Modification of Boron Monoxide". J. Am. Chem. Soc. 77 (23): 6400–6401. doi:10.1021/ja01628a116.