1,1,3,3-Tetramethylguanidine

1,1,3,3-Tetramethylguanidine

Names
IUPAC name 1,1,3,3-Tetramethylguanidine
Identifiers
CAS Number	80-70-6 N
3D model (Jmol)	Interactive image Interactive image
Beilstein Reference	969608
ChemSpider	59832 Y
ECHA InfoCard	100.001.185
EC Number	201-302-7
MeSH	1,1,3,3-tetramethylguanidine
PubChem	66460
UN number	2920
InChI InChI=1S/C5H13N3/c1-7(2)5(6)8(3)4/h6H,1-4H3 Y Key: KYVBNYUBXIEUFW-UHFFFAOYSA-N Y
SMILES C[n](C):c(:[nH]):[n](C)C CN(C)C(=N)N(C)C
Properties
Chemical formula	C5H13N3
Molar mass	115.18 g·mol−1
Appearance	Colourless liquid
Density	918 mg mL−1
Melting point	−30 °C (−22 °F; 243 K)
Boiling point	160 to 162 °C (320 to 324 °F; 433 to 435 K)
Solubility in water	Miscible
Vapor pressure	30 Pa (at 20 °C)
Acidity (pKa)	13.0±1.0 (pKa of conjugate acid in water)
Refractive index (nD)	1.469
Hazards
GHS pictograms
GHS signal word	DANGER
GHS hazard statements	H226, H302, H314
GHS precautionary statements	P280, P305+351+338, P310
EU classification (DSD)	C
R-phrases	R22, R34
S-phrases	S26, S27, S36/37/39, S45
Flash point	60 °C (140 °F; 333 K)
Explosive limits	1–7.5%
Related compounds
Related compounds	Dimethylurea Noxytiolin Metformin Allantoic acid Carmustine
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

Tetramethylguanidine is an organic compound with the formula HNC(N(CH₃)₂)₂. This colourless liquid is a strong base with a higher pK_a than typical amines.

It was originally prepared from tetramethylthiourea via S-methylation and amination, but alternative methods start from cyanogen iodide.

TMG is mainly used as a strong, non-nucleophilic base for alkylations, often as a substitute for the more expensive bases DBU and DBN. Since it is highly water-soluble, it is easily removed from mixtures in organic solvents. It is also used as a base-catalyst in the production of polyurethane.