1,1,3,3-Tetramethylurea

Synonym(s):1,1,3,3-Tetramethylurea;TMU

CAS NO.：632-22-4
Empirical Formula: C5H12N2O
Molecular Weight: 116.16
MDL number: MFCD00008319
EINECS: 211-173-9
SAFETY DATA SHEET (SDS)
Update Date: 2026-01-13 11:14:01

What is 1,1,3,3-Tetramethylurea?

Chemical properties

Tetramethylurea is a clear colorless to pale yellow liquid with mild aromatic odor that is miscible with water and many organic solvents. Unusual for an urea is the liquid state of tetramethylurea in a range of > 170 °C.

The Uses of 1,1,3,3-Tetramethylurea

Tetramethylurea is used as a solvent in dyestuff industries, in condensation reaction and intermediates in surfactant. It is utilized for base catalyzed isomerization and alkylation hydrocyanation due to its low permittivity. It reacts with oxalyl chloride to prepare tetramethyl chloroformamidinium chloride, which is used for the conversion of carboxylic acids and dialkyl phosphates to anhydrides and pyrophosphates respectively.

Definition

ChEBI: 1,1,3,3-tetramethylurea is a member of the class of ureas that is urea substituted by methyl groups at positions 1, 1, 3 and 3 respectively. Metabolite observed in cancer metabolism. It has a role as a human metabolite.

Preparation

The reaction of dimethylamine with phosgene in the presence of e. g. 50 % sodium hydroxide solution and subsequent extraction with 1,2-dichloroethane yields tetramethylurea in 95% yield.

Safety Profile

Moderately toxic by ingestion and intravenous routes. An experimental teratogen. Experimental reproductive effects. Human mutation data reported. Combustible when exposed to heat, flame, and oxidizers. To fight fire, use foam, mist, spray, dry chemicals. When heated to decomposition it emits toxic fumes of NOx.

Purification Methods

Dry it over BaO and distil it under nitrogen. It denatures proteins in H2O. [Elbaum & Herskovits Biochemistry 13 1268 1974, Kane Anal Biochem 53 350 1973, Beilstein 4 IV 225.]

Properties of 1,1,3,3-Tetramethylurea

Melting point:	−1 °C(lit.)
Boiling point:	177 °C(lit.)
Density	0.968 g/mL at 20 °C(lit.)
refractive index	n20/D 1.451(lit.)
Flash point:	150 °F
storage temp.	Inert atmosphere,Room Temperature
solubility	Miscible with water, petroleum ether and common solvents.
form	Liquid
pka	2.0(at 25℃)
color	Clear colorless to pale yellow
Relative polarity	5
Odor	faint pleasant odor
PH	5-8 (25℃, 1M in H2O)
Water Solubility	H2O: 1 M at 20 °C, miscible
Merck	14,9230
BRN	773898
Dielectric constant	24.460000000000001
CAS DataBase Reference	632-22-4(CAS DataBase Reference)
NIST Chemistry Reference	Urea, tetramethyl-(632-22-4)
EPA Substance Registry System	Tetramethylurea (632-22-4)

Safety information for 1,1,3,3-Tetramethylurea

Signal word	Danger
Pictogram(s)	Corrosion Corrosives GHS05 Exclamation Mark Irritant GHS07 Health Hazard GHS08
GHS Hazard Statements	H302:Acute toxicity,oral H315:Skin corrosion/irritation H318:Serious eye damage/eye irritation
Precautionary Statement Codes	P202:Do not handle until all safety precautions have been read and understood. P280:Wear protective gloves/protective clothing/eye protection/face protection. P301+P312:IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell. P302+P352:IF ON SKIN: wash with plenty of soap and water. P305+P351+P338:IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing. P308+P313:IF exposed or concerned: Get medical advice/attention.