1,8-Diazabicyclo(5.4.0)undec-7-ene

Last updated
1,8-Diazabicyclo[5.4.0]undec-7-ene
DBU.svg
DBU-3D-balls.png
Names
Preferred IUPAC name
2,3,4,6,7,8,9,10-Octahydropyrimido[1,2-a]azepine
Other names
DBU, Diazabicycloundecene
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.027.013 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 229-713-7
PubChem CID
UNII
  • InChI=1S/C9H16N2/c1-2-5-9-10-6-4-8-11(9)7-3-1/h1-8H2 Yes check.svgY
    Key: GQHTUMJGOHRCHB-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C9H16N2/c1-2-5-9-10-6-4-8-11(9)7-3-1/h1-8H2
    Key: GQHTUMJGOHRCHB-UHFFFAOYAM
  • N\2=C1\N(CCCCC1)CCC/2
Properties
C9H16N2
Molar mass 152.241 g·mol−1
AppearanceColorless liquid
Density 1.018 g/mL liquid[ citation needed ]
Melting point −70 °C (−94 °F; 203 K)
Boiling point 261 °C (502 °F; 534 K) (1 atm),
80 to 83 °C (0.6 mmHg)
ethers, alcohols
Acidity (pKa)13.5±1.5 [1] (pKa of conjugate acid in water); 24.34 [2] (pKa of conjugate acid in acetonitrile)
Hazards
GHS labelling:
GHS-pictogram-acid.svg GHS-pictogram-skull.svg GHS-pictogram-exclam.svg
Danger
H301, H302, H312, H314, H412
P260, P264, P270, P273, P280, P301+P310, P301+P312, P301+P330+P331, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P321, P322, P330, P363, P405, P501
Flash point 119.9 °C (247.8 °F; 393.0 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

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. [3]

Contents

Synthesis

DBU can be synthesised in three steps from caprolactam and acrylonitrile. First, the nitrile undergoes an addition reaction at the caprolactam nitrogen, producing N-(2-cyanoethyl)-caprolactam. This is then hydrogenated to N-aminopropyl-caprolactam, followed by an intramolecular carbonyl condensation to form the imine. Water is removed by fractional distillation. [4]

Occurrence

Although all commercially available DBU is produced synthetically, it may also be isolated from the sea sponge Niphates digitalis . [5] The biosynthesis of DBU has been proposed to begin with adipaldehyde and 1,3-diaminopropane.

Proposed pathway for the biosynthesis of DBU in sponges. REGALADO DBU BIOSYNTHETIC HYPOTHESIS.png
Proposed pathway for the biosynthesis of DBU in sponges.

Applications

DBU is used:

See also

References

  1. Kaupmees, K.; Trummal, A.; Leito, I. (2014). "Basicities of Strong Bases in Water: A Computational Study". Croat. Chem. Acta. 87 (4): 385–395. doi: 10.5562/cca2472 .
  2. Kaljurand, I.; Kütt, A.; Sooväli, L.; Rodima, T.; Mäemets, V.; Leito, I.; Koppel, I. A. (2005). "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. 70 (3): 1019–1028. doi:10.1021/jo048252w. PMID   15675863.
  3. Ghosh, Nandita (2004). "DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) - A Nucleophillic Base". Synlett (3): 574–575. doi: 10.1055/s-2004-815436 .
  4. CNpatent 101279973,Bi Zuowen, Gao Hongbin, Cao Hongbo, Wang Xiaomei, Liu Change, Xu Qin, Zhang Zonghua,"Preparation of 1,8-diazabicyclo[5.4.0]undec-7-ene",issued 2010-06-02, assigned to Shandong Xinhua Wanbo Chemical
  5. 1 2 E. L. Regalado; Judith Mendiola; Abilio Laguna; Clara Nogueiras; Olivier P Thomas (2010). "Polar alkaloids from the Caribbean marine sponge Niphates digitalis". Nat. Prod. Commun. 5 (8): 1187–1190. PMID   20839615.
  6. Parviainen, Arno; King, Alistair W. T.; Mutikainen, Ilpo; Hummel, Michael; Selg, Christoph; Hauru, Lauri K. J.; Sixta, Herbert; Kilpeläinen, Ilkka (2013). "Predicting Cellulose Solvating Capabilities of Acid–Base Conjugate Ionic Liquids". ChemSusChem. 6 (11): 2161–2169. Bibcode:2013ChSCh...6.2161P. doi:10.1002/cssc.201300143. ISSN   1864-5631. PMID   24106149.
  7. Romero, Erik A.; Zhao, Tianxiang; Nakano, Ryo; Hu, Xingbang; Wu, Youting; Jazzar, Rodolphe; Bertrand, Guy (2018-10-01). "Tandem copper hydride–Lewis pair catalysed reduction of carbon dioxide into formate with dihydrogen". Nature Catalysis. 1 (10): 743–747. doi:10.1038/s41929-018-0140-3. ISSN   2520-1158.
  8. Savoca, Ann C.; Urgaonkar, Sameer (2006). "1,8-Diazabicyclo[5.4.0]undec-7-ene". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rd011.pub2. ISBN   0-471-93623-5.
  9. "Novatio Silfix Primer SDS" (PDF). novatio.com. 2022. Archived from the original (PDF) on 2025-05-16. Retrieved 2025-05-16.