7-Methyl-1,5,7-triazabicyclo(4.4.0)dec-5-ene

7-Methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (mTBD) is a bicyclic strong guanidine base (pK_a = 25.43 in CH₃CN and pK_a = 17.9 in THF).[3] mTBD, like 1,5,7-triazabicyclo[4.4.0]dec-5-ene and other guanidine super bases, can be used as a catalyst in a variety of chemical reactions.[4] It also reacts with CO₂, which could make it useful for carbon capture and storage.[5]

7-Methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene[1]

Names
IUPAC name 1-Methyl-2,3,4,6,7,8-hexahydropyrimido[1,2-a]pyrimidine
Other names mTBD; 7-Methyl-TBD; 7-Methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene; 1,3,4,6,7,8-Hexahydro-1-methyl-2H-pyrimido[1,2-a]pyrimidine
Identifiers
CAS Number	84030-20-6^N
3D model (JSmol)	Interactive image
ChemSpider	110177^Y
ECHA InfoCard	100.074.332
EC Number	281-791-1
PubChem CID	123583
CompTox Dashboard (EPA)	DTXSID70232932
InChI InChI=1S/C8H15N3/c1-10-5-3-7-11-6-2-4-9-8(10)11/h2-7H2,1H3 Key: OEBXWWBYZJNKRK-UHFFFAOYSA-N
SMILES CN1CCCN2C1=NCCC2
Properties
Chemical formula	C8H15N3
Molar mass	153.225 g/mol
Appearance	clear liquid[2]
Density	1063.35 kg/m^3[2]
Melting point	17[2] °C (63 °F; 290 K)
Boiling point	263[2] °C (505 °F; 536 K)
Thermal conductivity	0.144 W/m/K[2]
Refractive index (nD)	1.5357[2]
Viscosity	7.1 cP[2]
Hazards
GHS pictograms
GHS Signal word	Danger
GHS hazard statements	H314
GHS precautionary statements	P260, P264, P280, P301+330+331, P303+361+353, P304+340, P305+351+338, P310, P321, P363, P405, P501
Thermochemistry
Heat capacity (C)	1.75 J/g/K[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N (what is ^YN ?)
Infobox references

When brought into contact with some acids, mTBD reacts to form an ionic liquid. Some of these ionic liquids can dissolve cellulose.[6]

References

1. 7-Methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene at PubChem
2. Baird, Zachariah Steven; Dahlberg, Artur; Uusi-Kyyny, Petri; Osmanbegovic, Nahla; Witos, Joanna; Helminen, Jussi; Cederkrantz, Daniel; Hyväri, Paulus; Alopaeus, Ville; Kilpeläinen, Ilkka; Wiedmer, Susanne K.; Sixta, Herbert (2019). "Physical properties of 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (mTBD)". International Journal of Thermophysics. 40 (71). doi:10.1007/s10765-019-2540-2.
3. Ishikawa, T. (2009). Superbases for Organic Synthesis: Guanidines, Amidines, Phosphazenes and Related Organocatalysts. John Wiley & Sons. ISBN 9780470740866.
4. Simoni, D.; Rondanin, R.; Morini, M.; Baruchello, R.; Invidiata, F. P. (2000). "1,5,7- Triazabicyclo[4.4.0]Dec-1-Ene (TBD), 7-Methyl-TBD (MTBD) and the PolymerSupported TBD (P-TBD): Three Efficient Catalysts for the Nitroaldol (Henry) Reaction and for the Addition of Dialkyl Phosphites to Unsaturated Systems". Tetrahedron Lett. 41 (10): 1607–1610. doi:10.1016/S0040-4039(99)02340-0.
5. Yang, Z.-Z.; Zhao, Y.-N.; He, L.-N. (2011). "CO2 Chemistry: Task-Specific Ionic Liquids for CO2 Capture/ Activation and Subsequent Conversion". RSC Adv. 1 (4): 545–567. doi:10.1039/C1RA00307K.
6. Parviainen, A.; King, A. W. T.; Mutikainen, I.; Hummel, M.; Selg, C.; Hauru, L. K. J.; Sixta, H.; Kilpeläinen, I. (2013). "Predicting Cellulose Solvating Capabilities of Acid–Base Conjugate Ionic Liquids". ChemSusChem. 6 (11): 2161–2169. doi:10.1002/cssc.201300143.