Bis(pinacolato)diboron

Bis(pinacolato)diboron
Names
IUPAC name
4,4,4',4',5,5,5',5'-Octamethyl-2,2'-bi-(1,3,2-dioxaborolane)
Identifiers
73183-34-3 YesY
3D model (Jmol) Interactive image
Abbreviations B2pin2
ChemSpider 2015334 N
ECHA InfoCard 100.111.245
PubChem 2733548
Properties
C12H24B2O4
Molar mass 253.94 g·mol−1
Melting point 137 to 140 °C (279 to 284 °F; 410 to 413 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YesYN ?)
Infobox references

Bis(pinacolato)diboron is covalent compound containing two boron atoms and two pinacolato ligands. It has the formula [(CH3)4C2O2B]2; the pinacol groups are sometimes abbreviated as "pin", so the structure is sometimes represented as B2pin2. It is a colourless solid that is soluble in organic solvents. It is a commercially available reagent for making pinacol boronic esters for organic synthesis. Unlike some other diboron compounds, B2pin2 is not moisture-sensative and can be handled in air.[1]

Preparation and structure

This compound may be prepared by reacting tetrakis(dimethylamino)diboron with pinacol in acidic conditions.[1] The B-B bond distance is 1.711(6) Å.[2]

Reactions

The B-B bond adds across alkenes and alkynes to give the 1,2-diborylated alkanes and alkenes. Using various organorhodium or organoiridium catalysts, it can also be installed onto saturated hydrocarbons:[3]

CH3(CH2)6CH3 + [pinB]2 → pinBH + CH3(CH2)7Bpin

References

  1. 1 2 Tatsuo Ishiyama; Miki Murata; Taka-aki Ahiko; Norio Miyaura (2004). "Bis(pinacolato)diboron". Org. Synth.; Coll. Vol., 10, p. 115
  2. C.Kleeberg, A.G.Crawford, A.S.Batsanov, P.Hodgkinson, D.C.Apperley, Man Sing Cheung, Zhenyang Lin, T.B.Marder "Spectroscopic and Structural Characterization of the CyNHC Adduct of B2pin2 in Solution and in the Solid State" J. Org. Chem 2012, vol. 77, pp. 785. doi:10.1021/jo202127c
  3. Xinyu Liu "Bis(pinacolato)diboron" Synlett 2003, pp 2442–2443. doi:10.1055/s-2003-43344
This article is issued from Wikipedia - version of the 11/30/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.