1,5-Diazabicyclo[4.3.0]non-5-ene (DBN) is a chemical compound with the formula C7H12N2.[1] It is an amidine base used in organic synthesis. A related compound with related functions is 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). The relatively complex nature of the formal names for DBU and DBN (hence the common use of acronyms) reflects the fact that these compounds are bicyclic and contain several functional groups.

DBN molecule
Preferred IUPAC name
Other names
  • 3001-72-7 checkY
3D model (JSmol)
  • Interactive image
  • 68826 ☒N
ECHA InfoCard 100.019.171 Edit this at Wikidata
EC Number
  • 221-087-3
  • 76349
  • 978M4OL12Q
  • DTXSID10184087 Edit this at Wikidata
  • InChI=1S/C7H12N2/c1-3-7-8-4-2-6-9(7)5-1/h1-6H2 ☒N
  • InChI=1/C9H12N2/c10-11-8-4-2-6-9(11)5-1-3-7(8)9/h1-6H2
  • InChI=1S/C9H12N2/c10-11-8-4-2-6-9(11)5-1-3-7(8)9/h1-6H2
  • C1CC2=NCCCN2C1
Molar mass 124.18 g/mol
Density 1.005 g/cm3
Boiling point 95 to 98 °C (203 to 208 °F; 368 to 371 K) at 7.5 mmHg
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references


DBN could be synthesized in the following manner, similarly to DBU:[2]


The synthetic procedure starts with a Michael addition of 2-pyrrolidone to acrylonitrile, followed by hydrogenation, and finally dehydration.


As a base in organic synthesisEdit

Similar to many other organic bases, DBN could be employed for dehydrohalogenation reactions, base-catalyzed rearrangement reactions, as well as Aldol condensation.[3] Several examples are shown below:

  • Elimination:[2]
  • Aldol condensation:[5]

DBN salt as an ionic liquidEdit

The acetate salt of DBN is a room-temperature ionic liquid used for processing cellulose fibers by acting as a replacement for the unstable N-Methylmorpholine N-oxide used for making lyocell.[6][7]


  1. ^ Savoca, Ann. C. "1,5-Diazabicyclo[4.3.0]non-5-ene" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. doi:10.1002/047084289X.rd010.pub2
  2. ^ a b Möller, F.; Oediger, H. "1,5-Diazabicyclo[5.4.0]undec-5-ene, a New Hydrogen Halide Acceptor" Angew. Chem. Int. Ed. Engl. , 1967, 5, 76. doi:10.1002/anie.196700761
  3. ^ Oediger, H., Möller, F., & Eiter, K. "Bicyclic Amidines as Reagents in Organic Syntheses" Synthesis, 1972, 11, 591–598. doi:10.1055/s-1972-21943
  4. ^ Jackson, J.R. and Stoodley, R.J. "Equilibration of penicillanic acid derivatives" J. Chem. Soc. D, 1971, 647-648
  5. ^ Corey, E.J., Andersen, N.H., Carlson, R.M. "Total synthesis of prostaglandins. Synthesis of the pure dl-E1, -F, -F, -A1, and -B1 hormones" J. Am. Chem. Soc., 1968, 90, 12, 3245–3247 doi:10.1021/ja01014a053
  6. ^ Zhang, Jinming; Wu, Jin; Yu, Jian; Zhang, Xiaoyu; He, Jiasong; Zhang, Jun. "Application of ionic liquids for dissolving cellulose and fabricating cellulose-based materials: state of the art and future trends." Mat. Chem. Front. 2017, 1 (7), 1273-90. doi:10.1039/C6QM00348F
  7. ^ Ioncell - Enter the new era of textile production!