9-Borabicyclo(3.3.1)nonane

Last updated
9-Borabicyclo[3.3.1]nonane
9-BBN dimer structure.svg
9-BBN-dimer-xtal-3D-sticks-skeletal.png
BBN Crystals.jpg
Names
IUPAC name
9-Borabicyclo[3.3.1]nonane
Other names
Borabicyclononane
Banana borane
Identifiers
3D model (JSmol)
Abbreviations9-BBN
ChemSpider
ECHA InfoCard 100.005.456 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 206-000-9
PubChem CID
UNII
  • InChI=1S/C8H15B/c1-3-7-5-2-6-8(4-1)9-7/h7-9H,1-6H2 Yes check.svgY
    Key: FEJUGLKDZJDVFY-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C8H15B/c1-3-7-5-2-6-8(4-1)9-7/h7-9H,1-6H2
    Key: FEJUGLKDZJDVFY-UHFFFAOYAE
  • B1([H]3)(C2CCCC1CCC2)[H]B34C2CCCC4CCC2
Properties
C16H30B2
Molar mass 244.04 g·mol−1
Density 0.894 g/cm3
Melting point 153 to 155 °C (307 to 311 °F; 426 to 428 K)
Reacts
Hazards
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-acid.svg
Warning
H250, H260, H314
P210, P222, P223, P231+P232, P260, P264, P280, P301+P330+P331, P302+P334, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P335+P334, P363, P370+P378, P402+P404, P405, P422, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

9-Borabicyclo[3.3.1]nonane or 9-BBN is an organoborane compound. This colourless solid is used in organic chemistry as a hydroboration reagent. The compound exists as a hydride-bridged dimer, which easily cleaves in the presence of reducible substrates. [1] 9-BBN is also known by its nickname 'banana borane'. [2] This is because rather than drawing out the full structure, chemists often simply draw a banana shape with the bridging boron. [3] [ better source needed ]

Contents

Preparation

9-BBN is prepared by the reaction of 1,5-cyclooctadiene and borane usually in ethereal solvents, for example: [4] [5]

Synthesis of 9-BBN dimer.png

The compound is commercially available as a solution in tetrahydrofuran and as a solid. 9-BBN is especially useful in Suzuki reactions. [6] [7] [8]

Its highly regioselective addition on alkenes allows the preparation of terminal alcohols by subsequent oxidative cleavage with H2O2 in aqueous KOH. The steric demand of 9-BBN greatly suppresses the formation of the 2-substituted isomer compared to the use of borane.

See also

Related Research Articles

<span class="mw-page-title-main">Boranes</span>

A borane is a compound with the formula BxHy or a related anion. Many such boranes are known. Most common are those with 1 to 12 boron atoms. Although they have few practical applications, the boranes exhibit structures and bonding that differs strongly from the patterns seen in hydrocarbons. Hybrids of boranes and hydrocarbons, the carboranes are also well developed.

In organic chemistry, the Swern oxidation, named after Daniel Swern, is a chemical reaction whereby a primary or secondary alcohol is oxidized to an aldehyde or ketone using oxalyl chloride, dimethyl sulfoxide (DMSO) and an organic base, such as triethylamine. It is one of the many oxidation reactions commonly referred to as 'activated DMSO' oxidations. The reaction is known for its mild character and wide tolerance of functional groups.

Hydroboration–oxidation reaction is a two-step hydration reaction that converts an alkene into an alcohol. The process results in the syn addition of a hydrogen and a hydroxyl group where the double bond had been. Hydroboration–oxidation is an anti-Markovnikov reaction, with the hydroxyl group attaching to the less-substituted carbon. The reaction thus provides a more stereospecific and complementary regiochemical alternative to other hydration reactions such as acid-catalyzed addition and the oxymercuration–reduction process. The reaction was first reported by Herbert C. Brown in the late 1950s and it was recognized in his receiving the Nobel Prize in Chemistry in 1979.

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

Diborane(6), commonly known as diborane, is the chemical compound with the formula B2H6. It is a toxic, colorless, and pyrophoric gas with a repulsively sweet odor. Given its simple formula, borane is a fundamental boron compound. It has attracted wide attention for its electronic structure. Several of its derivatives are useful reagents.

The Suzuki reaction is an organic reaction, classified as a cross-coupling reaction, where the coupling partners are a boronic acid and an organohalide and the catalyst is a palladium(0) complex. It was first published in 1979 by Akira Suzuki, and he shared the 2010 Nobel Prize in Chemistry with Richard F. Heck and Ei-ichi Negishi for their contribution to the discovery and development of palladium-catalyzed cross-couplings in organic synthesis. This reaction is also known as the Suzuki–Miyaura reaction or simply as the Suzuki coupling. It is widely used to synthesize polyolefins, styrenes, and substituted biphenyls. Several reviews have been published describing advancements and the development of the Suzuki reaction. The general scheme for the Suzuki reaction is shown below, where a carbon-carbon single bond is formed by coupling a halide (R1-X) with an organoboron species (R2-BY2) using a palladium catalyst and a base. The organoboron species is usually synthesized by hydroboration or carboboration, allowing for rapid generation of molecular complexity.

<span class="mw-page-title-main">Organoboron chemistry</span> Study of compounds containing a boron-carbon bond

Organoboron chemistry or organoborane chemistry studies organoboron compounds, also called organoboranes. These chemical compounds combine boron and carbon; typically, they are organic derivatives of borane (BH3), as in the trialkyl boranes.

In organic chemistry, hydroboration refers to the addition of a hydrogen-boron bond to certain double and triple bonds involving carbon. This chemical reaction is useful in the organic synthesis of organic compounds.

<span class="mw-page-title-main">Pinene</span> Oily organic chemical found in plants

Pinene is a collection of unsaturated bicyclic monoterpenes. Two geometric isomers of pinene are found in nature, α-pinene and β-pinene. Both are chiral. As the name suggests, pinenes are found in pines. Specifically, pinene is the major component of the liquid extracts of conifers. Pinenes are also found in many non-coniferous plants such as camphorweed (Heterotheca) and big sagebrush.

Cycloocta-1,5-diene is a cyclic hydrocarbon with the chemical formula C8H12, specifically [−(CH2)2−CH=CH−]2.

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

Ammonia borane, also called borazane, is the chemical compound with the formula H3NBH3. The colourless or white solid is the simplest molecular boron-nitrogen-hydride compound. It has attracted attention as a source of hydrogen fuel, but is otherwise primarily of academic interest.

<span class="mw-page-title-main">Boronic acid</span> Organic compound of the form R–B(OH)2

A boronic acid is an organic compound related to boric acid in which one of the three hydroxyl groups is replaced by an alkyl or aryl group. As a compound containing a carbon–boron bond, members of this class thus belong to the larger class of organoboranes.

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

Phenylboronic acid or benzeneboronic acid, abbreviated as PhB(OH)2 where Ph is the phenyl group C6H5-, is a boronic acid containing a phenyl substituent and two hydroxyl groups attached to boron. Phenylboronic acid is a white powder and is commonly used in organic synthesis. Boronic acids are mild Lewis acids which are generally stable and easy to handle, making them important to organic synthesis.

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

Disiamylborane is an organoborane with the formula [( 2CHCH )2BH]2. It is a colorless waxy solid that is used in organic synthesis for hydroboration–oxidation reactions. Like most dialkyl boron hydrides, it has a dimeric structure with bridging hydrides.

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

Diisopinocampheylborane is an organoborane that is useful for asymmetric synthesis. This colourless solid is the precursor to a range of related reagents. The compound was reported in 1961 by Zweifel and Brown in a pioneering demonstration of asymmetric synthesis using boranes. The reagent is mainly used for the synthesis of chiral secondary alcohols. The reagent is often depicted as a monomer but like most hydroboranes, it is dimeric with B-H-B bridges.

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

Alpine borane is the commercial name for an organoboron compound that is used in organic synthesis. It is a colorless liquid, although it is usually encountered as a solution.

<span class="mw-page-title-main">3-Hydroxytetrahydrofuran</span> Chemical compound

3-Hydroxytetrahydrofuran is a colorless liquid with a normal boiling point of 179 °C and boiling at 88−89 °C at 17 mmHg, with density. 3-OH THF is a useful pharmaceutical intermediate. The chiral version of this compound is an intermediate to launched retroviral drugs.

<span class="mw-page-title-main">Borane–tetrahydrofuran</span> Chemical compound

Borane–tetrahydrofuran is an adduct derived from borane and tetrahydrofuran (THF). These solutions, which are colorless, are used for reductions and hydroboration, reactions that are useful in synthesis of organic compounds. The use of borane–tetrahydrofuran has been displaced by borane–dimethylsulfide, which has a longer shelf life and effects similar transformations.

Borane, also known as borine, is an unstable and highly reactive molecule with the chemical formula BH
3
. The preparation of borane carbonyl, BH3(CO), played an important role in exploring the chemistry of boranes, as it indicated the likely existence of the borane molecule. However, the molecular species BH3 is a very strong Lewis acid. Consequently, it is highly reactive and can only be observed directly as a continuously produced, transitory, product in a flow system or from the reaction of laser ablated atomic boron with hydrogen. It normally dimerizes to diborane in the absence of other chemicals.

Metal-catalyzed C–H borylation reactions are transition metal catalyzed organic reactions that produce an organoboron compound through functionalization of aliphatic and aromatic C–H bonds and are therefore useful reactions for carbon–hydrogen bond activation. Metal-catalyzed C–H borylation reactions utilize transition metals to directly convert a C–H bond into a C–B bond. This route can be advantageous compared to traditional borylation reactions by making use of cheap and abundant hydrocarbon starting material, limiting prefunctionalized organic compounds, reducing toxic byproducts, and streamlining the synthesis of biologically important molecules. Boronic acids, and boronic esters are common boryl groups incorporated into organic molecules through borylation reactions. Boronic acids are trivalent boron-containing organic compounds that possess one alkyl substituent and two hydroxyl groups. Similarly, boronic esters possess one alkyl substituent and two ester groups. 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 formula (RO)2B-B(OR)2. For example, bis(pinacolato)diboron (B2Pin2), and bis(catecholato)diborane (B2Cat2) are common boron sources of this general formula.

Norio Miyaura was a Japanese organic chemist. He was a professor of graduate chemical engineering at Hokkaido University. His major accomplishments surrounded his work in cross-coupling reactions / conjugate addition reactions of organoboronic acids and addition / coupling reactions of diborons and boranes. He is also the co-author of Cross-Coupling Reactions: A Practical Guide with M. Nomura E. S.. Miyaura was a world-known and accomplished researcher by the time he retired and so, in 2007, he won the Japan Chemical Society Award.

References

  1. Brown, H. C. (1975). Organic Syntheses via Boranes . New York: John Wiley & Sons. ISBN   0-471-11280-1.
  2. Stix, Gary. "The Straight Dope: A Q&A with the Prof behind the Good Science in Breaking Bad". Scientific American Blog Network. Nature America, Inc. Retrieved 18 June 2017.
  3. "Molecules with Silly or Unusual Names - page 3". Chm.bris.ac.uk. 2014-05-07. Retrieved 2016-06-01.
  4. Soderquist, John A.; Brown, Herbert C. (1981). "Simple, remarkably efficient route to high purity, crystalline 9-borabicyclo[3.3.1]nonane (9-BBN) dimer". J. Org. Chem. 46 (22): 4599–4600. doi:10.1021/jo00335a067.
  5. Soderquist, John A.; Alvin, Negron (1982). "9-Borabicyclo[3.3.1]nonane Dimer". Organic Syntheses . 70: 169. doi:10.15227/orgsyn.070.0169.
  6. Ishiyama, Tatsuo; Miyaura, Norio; Suzuki, Akira. "Palladium(0)-catalyzed reaction of 9-alkyl-9-borabicyclo[3.3.1]nonane with 1-bromo-1-phenylthioethene: 4-(3-cyclohexenyl)-2-phenylthio-1-butene". Organic Syntheses .; Collective Volume, vol. 9, p. 107
  7. Balog, A.; Meng, D.; Kamenecka, T.; Bertinato, P.; Su, D.-S.; Sorensen, E. J.; Danishefsky, S. J. (1996). "Total Synthesis of (−)-Epothilone A". Angew. Chem. Int. Ed. Engl. 35 (2324): 2801. doi:10.1002/anie.199628011.
  8. Liu, J.; Lotesta, S. D.; Sorensen, E. J. (2011). "A concise synthesis of the molecular framework of pleuromutilin". Chem. Commun. 47 (5): 1500–1502. doi:10.1039/C0CC04077K. PMC   3156455 . PMID   21079876.