1,8-Diazabicycloundec-7-ene

1,8-Diazabicycloundec-7-ene
1,8-Diazabicyclo[5.4.0]undec-7-ene
Identifiers
CAS number 6674-22-2 YesY
ChemSpider 73246 YesY
Jmol-3D images Image 1
Properties
Molecular formula C9H16N2
Molar mass 152.24 g/mol
Appearance Colorless liquid
Density 1.018 g/mL liquid
Melting point

-70 °C, 203 K, -94 °F

Boiling point

80-83 °C (0.6 mmHg)

Acidity (pKa) 24.34 (in acetonitrile)[1] (pKa value of protonated DBU)
Hazards
R-phrases R22 R34
S-phrases S24 S25
Flash point 119.9°C
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

1,8-Diazabicyclo[5.4.0]undec-7-ene, or more commonly DBU, is a chemical compound and belongs to the class of amidine compounds. It is used in organic synthesis as a catalyst and complexing ligand and a strong (pKa = 24.34 in acetonitrile[1]) non-nucleophilic base.[2]

It is used as a curing agent for epoxy; it is used as a protecting agent for the synthesis of cephalosporin. It is used in fullerene purification with trimethylbenzene (it reacts to C70 and higher fullerenes but not to C60 fullerenes); and it is also used as a catalyst for polyurethane. It has a strong catalyst effect for the reactions of alicyclic and aliphatic isocyanates.

See also

References

  1. ^ a b I. Kaljurand, A. Kütt, L. Sooväli, T. Rodima, V. Mäemets, I. Leito, I. A. Koppel. Extension of the Self-Consistent Spectrophotometric Basicity Scale in Acetonitrile to a Full Span of 28 pKa Units: Unification of Different Basicity Scales. J. Org. Chem., 2005, 70, 1019–1028. DOI: 10.1021/jo048252w
  2. ^ Superbases for organic synthesis: guanidines, amidines and phosphazenes and related organocatalysts. T. Ishikawa, ed. Wiley, Chichester, 2009.