1,8-Diazabicycloundec-7-ene

1,8-Diazabicyclo[5.4.0]undec-7-ene
IUPAC name 2,3,4,6,7,8,9,10-octahydropyrimido[1,2-a]azepine
Other names DBU,Diazabicycloundecene
Identifiers
CAS number	6674-22-2 Y
ChemSpider	73246 Y
Jmol-3D images	Image 1
SMILES N\2=C1\N(CCCCC1)CCC/2
InChI InChI=1S/C9H16N2/c1-2-5-9-10-6-4-8-11(9)7-3-1/h1-8H2 Y Key: GQHTUMJGOHRCHB-UHFFFAOYSA-N Y InChI=1/C9H16N2/c1-2-5-9-10-6-4-8-11(9)7-3-1/h1-8H2 Key: GQHTUMJGOHRCHB-UHFFFAOYAM
Properties
Molecular formula	C9H16N2
Molar mass	152.24 g/mol
Appearance	Colorless liquid
Density	1.018 g/mL liquid
Melting point	−70 °C; −94 °F; 203 K
Boiling point	80-83 °C (0.6 mmHg), 261 °C (1 atm)
Acidity (pKa)	~12 (value for protonated form, pKa of a free base is ~24 -> C-H bond dissociation)
Basicity (pKb)	? (basicity)
Hazards
R-phrases	R22 R34
S-phrases	S24 S25
Flash point	119.9 °C; 247.8 °F; 393.0 K
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 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, a complexing ligand, and a non-nucleophilic base.

This compound is also considered as an alkaloid isolated from the sponge Niphates digitalis.^[1]

Regalado hypothetic biosynthesis of DBU

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

• 1,5-Diazabicyclo[4.3.0]non-5-ene
• DABCO

References

1. ↑ Regalado, E.L. et al., Nat. Prod. Commun., 2010, 5, 1187- 1190