Pinacol

Last updated
Pinacol
Pinacol Pinacol-2D-skeletal.png
Pinacol
Ball-and-stick model of pinacol Pinacol-1-from-xtal-3D-bs-17.png
Ball-and-stick model of pinacol
Names
Preferred IUPAC name
2,3-Dimethylbutane-2,3-diol
Other names
2,3-Dimethyl-2,3-butanediol
Tetramethylethylene glycol
1,1,2,2-Tetramethylethylene glycol
Pinacone
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.000.849 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 200-933-5
PubChem CID
UNII
  • InChI=1S/C6H14O2/c1-5(2,7)6(3,4)8/h7-8H,1-4H3 Yes check.svgY
    Key: IVDFJHOHABJVEH-UHFFFAOYSA-N Yes check.svgY
  • CC(C)(O)C(C)(C)O
  • CC(C)(O)C(C)(C)O
Properties
C6H14O2
Molar mass 118.174 g/mol
AppearanceWhite solid
Density 0.967 g/cm3
Melting point 40 to 43 °C (104 to 109 °F; 313 to 316 K)
Boiling point 171 to 173 °C (340 to 343 °F; 444 to 446 K)
Hazards
GHS labelling:
GHS-pictogram-acid.svg GHS-pictogram-exclam.svg
Warning
H228, H315, H319, H335
P210, P240, P241, P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P370+P378, P403+P233, P405, P501
Flash point 77 °C (171 °F; 350 K)
Safety data sheet (SDS) External MSDS
Related compounds
Related compounds
Pinacolone
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 ?)

Pinacol is a branched alcohol which finds use in organic syntheses. It is a diol that has hydroxyl groups on vicinal carbon atoms. A white solid that melts just above room temperature, pinacol is notable for undergoing the pinacol rearrangement in the presence of acid and for being the namesake of the pinacol coupling reaction.

Contents

Preparation

It may be produced by the pinacol coupling reaction from acetone: [1]

Pinacol coupling of acetone.png

Reactions

As a vicinal diol, it can rearrange to pinacolone by the pinacol rearrangement, e.g., by heating with sulfuric acid: [2]

800px-Pinacol rearragement.png

Pinacol can be used with borane and boron trichloride to produce useful synthetic intermediates such as pinacolborane, bis(pinacolato)diboron, [3] and pinacolchloroborane.

See also

References

  1. Roger Adams and E. W. Adams. "Pinacol Hydrate". Organic Syntheses ; Collected Volumes, vol. 1, p. 459.
  2. G. A. Hill and E. W. Flosdorf (1941). "Pinacolone". Organic Syntheses ; Collected Volumes, vol. 1, p. 462.
  3. Tatsuo Ishiyama; Miki Murata; Taka-aki Ahiko; Norio Miyaura (2004). "Bis(pinacolato)diboron". Organic Syntheses ; Collected Volumes, vol. 10, p. 115.