9-Borabicyclo(3.3.1)nonane

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The correct title of this article is 9-Borabicyclo[3.3.1]nonane. The substitution or omission of any < > [ ] { } is because of technical restrictions.
9-Borabicyclo(3.3.1)nonane
9-BBN dimer structure.svg
9-BBN-dimer-xtal-3D-sticks-skeletal.png
BBN Crystals.jpg
Identifiers
Abbreviations 9-BBN
CAS number 21205-91-4 N
PubChem 24855264
ChemSpider 71299 YesY
EC number 206-000-9
Jmol-3D images Image 1
Properties
Molecular formula C16H30B2
Molar mass 244.03 g mol−1
Density 0.894 g/cm3
Melting point 153 to 155 °C (307 to 311 °F; 426 to 428 K)
Solubility in water Reacts
Hazards
R-phrases R11 R14/15 R36/37/38
S-phrases S7/9 S16 S33 S7/8 S26 S37/39
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 N (verify) (what is: YesY/N?)
Infobox references

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]

Preparation[edit]

9-BBN is prepared by the reaction of 1,5-cyclooctadiene and borane usually in ethereal solvents, for example:[2][3]

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.[4]

Its highly regioselective addition on olefins 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.

References[edit]

  1. ^ Brown, H. C. “Organic Syntheses via Boranes” John Wiley & Sons, Inc. New York: 1975. ISBN 0-471-11280-1.
  2. ^ John A. Soderquist, Herbert C. Brown (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. 
  3. ^ John A. Soderquist and Alvin Negron (1998), "9-Borabicyclo[3.3.1]nonane Dimer", Org. Synth. ; Coll. Vol. 9: 95 
  4. ^ (a)Tatsuo Ishiyama, Norio Miyaura, and Akira Suzuki, "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 ", Org. Synth. ; Coll. Vol. 9: 107 (b) A. Balog, D. Meng, T. Kamenecka, P. Bertinato, D.-S. Su, E.J. Sorensen and S.J. Danishefsky, "Total Synthesis of (–)-Epothilone A" Angew. Chem., Int. Ed. Engl., 1996, 35, 2801. doi:10.1002/anie.199628011 (c) J. Liu, S. D. Lotesta and E. J. Sorensen, "A concise synthesis of the molecular framework of pleuromutilin", Chem. Commun., 2011, 47, 1500. doi:10.1039/C0CC04077K

External links[edit]