9-BBN
Encyclopedia
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. Like other organoboron compounds, 9-BBN is pyrophoric.
and borane
usually in ethereal solvents, for example:
The compound is commercially available as a solution in tetrahydrofuran
and as a solid. 9-BBN is especially useful in Suzuki reaction
s.
Its highly stereoselective addition on olefins allows the preparation of terminal alcohols by subsequent oxidative cleavage with H2O2 in aq. KOH. The steric demand of 9-BBN greatly suppresses the formation of the 2-substituted isomer compared to the use of borane.
Organoborane
Organoborane or organoboron compounds are chemical compounds that are organic derivatives of BH3, for example trialkyl boranes. Organoboron chemistry or organoborane chemistry is the chemistry of these compounds...
compound. This colourless solid is used in organic chemistry
Organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...
as a hydroboration reagent
Reagent
A reagent is a "substance or compound that is added to a system in order to bring about a chemical reaction, or added to see if a reaction occurs." Although the terms reactant and reagent are often used interchangeably, a reactant is less specifically a "substance that is consumed in the course of...
. The compound exists as a hydride-bridged dimer, which easily cleaves in the presence of reducible substrates. Like other organoboron compounds, 9-BBN is pyrophoric.
Preparation
9-BBN is prepared by the reaction of 1,5-cyclooctadiene1,5-Cyclooctadiene
1,5-Cyclooctadiene is the organic compound with the chemical formula C8H12. Generally abbreviated COD, this diene is a useful precursor to other organic compounds and serves as a ligand in organometallic chemistry.- Synthesis :...
and borane
Borane
In chemistry, a borane is a chemical compound of boron and hydrogen. The boranes comprise a large group of compounds with the generic formulae of BxHy. These compounds do not occur in nature. Many of the boranes readily oxidise on contact with air, some violently. The parent member BH3 is called...
usually in ethereal solvents, for example:
The compound is commercially available as a solution in tetrahydrofuran
Tetrahydrofuran
Tetrahydrofuran is a colorless, water-miscible organic liquid with low viscosity at standard temperature and pressure. This heterocyclic compound has the chemical formula 4O. As one of the most polar ethers with a wide liquid range, it is a useful solvent. Its main use, however, is as a precursor...
and as a solid. 9-BBN is especially useful in Suzuki reaction
Suzuki reaction
The Suzuki reaction is the organic reaction of an aryl- or vinyl-boronic acid with an aryl- or vinyl-halide catalyzed by a palladium complex. It is widely used to synthesize poly-olefins, styrenes, and substituted biphenyls, and has been extended to incorporate alkyl bromides...
s.
Its highly stereoselective addition on olefins allows the preparation of terminal alcohols by subsequent oxidative cleavage with H2O2 in aq. KOH. The steric demand of 9-BBN greatly suppresses the formation of the 2-substituted isomer compared to the use of borane.