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

1,8-Diazabicyclo[5.4.0]undec-7-ene
Names
	Preferred 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 ;
3D model (JSmol)	Interactive image;
ChemSpider	73246 ;
ECHA InfoCard	100.027.013
EC Number	229-713-7;
PubChem CID	81184;
UNII	H1ILJ6IBUX;
CompTox Dashboard (EPA)	DTXSID2049424 ;
	InChI InChI=1S/C9H16N2/c1-2-5-9-10-6-4-8-11(9)7-3-1/h1-8H2 Key: GQHTUMJGOHRCHB-UHFFFAOYSA-N ; InChI=1/C9H16N2/c1-2-5-9-10-6-4-8-11(9)7-3-1/h1-8H2 Key: GQHTUMJGOHRCHB-UHFFFAOYAM;
	SMILES N\2=C1\N(CCCCC1)CCC/2;
Properties
Chemical formula	C9H16N2
Molar mass	152.241 g·mol−1
Appearance	Colorless liquid
Density	1.018 g/mL liquid
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)
Solubility in water	ethers, alcohols
Acidity (pKa)	13.5±1.5 (pKa of conjugate acid in water); 24.34 (pKa of conjugate acid in acetonitrile)
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H301, H302, H312, H314, H412
Precautionary statements	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). verify (what is ?) 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.^[3]

Occurrence

Although all commercially available DBU is produced synthetically, it may also be isolated from the sea sponge Niphates digitalis.^[4] The biosynthesis of DBU has been proposed to begin with adipaldehyde and 1,3-diaminopropane.

Proposed pathway for the biosynthesis of DBU in sponges.^[4]

Uses

As a reagent in organic chemistry, DBU is used as a ligand and base. As a base, protonation occurs at the imine nitrogen.^[5] Lewis acids also attach to the same nitrogen.^[6]

These properties recommend DBU for use as a catalyst, for example as a curing agent for epoxy resins and polyurethane.

It is used in the separation of fullerenes in conjunction with trimethylbenzene. It reacts with C₇₀ and higher fullerenes, but not with C₆₀.

It is useful for dehydrohalogenations.^[7]

References

^ 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.
^ 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.
^ 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.
^ ^a ^b 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.
^ 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.
^ 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.
^ 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.

[Kaupmees_CCA-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.

[Kaljurand_2005_JOC-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.

[Regalado-4] 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.

[5] 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.

[6] 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.

[7] 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.

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

Contents

Occurrence

Uses

See also

References