Dimethyl oxalate

Synonym(s):Dimethyl oxalate;Oxalic acid dimethyl ester, Methyl oxalate

CAS NO.：553-90-2
Empirical Formula: C4H6O4
Molecular Weight: 118.09
MDL number: MFCD00008442
EINECS: 209-053-6
SAFETY DATA SHEET (SDS)
Update Date: 2024-10-25 16:21:11

What is Dimethyl oxalate?

Description

Dimethyl oxalate is a chemical compound with formula (CH₃)₂(COO)₂. It is the dimethyl ester of oxalic acid.

General Description

Dimethyl oxalate (DMO), (CH3OCO)2 is an industrial chemical intermediate with versatile properties. DMO is used as a solvent and extraction agent to produce ethylene glycol, ethanol, oxalic acid, oxamide, dyes, and medicines. Besides, dimethyl carbonate (DMC), (CH3O)2CO is attracting lots of interest because of its excellent solubility, biodegradability and low toxicity. DMC could be used as a green solvent, as electrolytes in lithium batteries, as a potential fuel additive and for polycarbonate synthesis[1].

Chemical properties

colourless crystals

Chemical properties

The empirical formula of dimethyl oxalate is C4H6O4. It exists as a liquid between its pour point (52°C) and boiling point (163.4°C). It is soluble in ethanol and ether and slightly soluble in water.

The Uses of Dimethyl oxalate

Dimethyl oxalate is used as an alternate fuel in the direct oxidation fuel cell. It is involved in the catalytic hydrogenation using Cu/SiO22ub> to prepare ethylene glycol. It is also used in the selective gas-phase hydrogenation catalyzed by Ag/SiO2 to get the corresponding alcohol.

Definition

ChEBI: Methyl oxalate is a diester, a methyl ester and a member of dicarboxylic acids and O-substituted derivatives. It is functionally related to an oxalic acid.

Synthesis Reference(s)

The Journal of Organic Chemistry, 24, p. 261, 1959 DOI: 10.1021/jo01084a633

General Description

Dimethyl oxalate undergoes Cu/SiO₂ catalyzed hydrogenation to yield ethylene glycol. It undergoes selective gas-phase hydrogenation catalyzed by Ag/SiO₂to yield corresponding alcohol.

Purification Methods

Crystallise the ester repeatedly from EtOH. De-gas it under nitrogen at high vacuum and distil it. [Beilstein 2 IV 1847.]

References

[1] Chunzheng Wang. “Emerging Co-Synthesis of Dimethyl Oxalate and Dimethyl Carbonate Using Pd/Silicalite-1 Catalyst with Synergistic Interactions of Pd and Silanols.” SSRN Electronic Journal 71 1 (2023).

Properties of Dimethyl oxalate

Melting point:	50-54 °C (lit.)
Boiling point:	163.5 °C (lit.)
Density	1.148 g/mL at 25 °C (lit.)
vapor pressure	3 hPa (20 °C)
refractive index	n20/D 1.39(lit.)
Flash point:	167 °F
storage temp.	Store below +30°C.
solubility	ethanol: soluble50mg/mL, clear to very slightly hazy, colorless
form	Crystalline Solid
color	Colorless to white
Specific Gravity	1.148
PH	1 (60g/l, H2O, 20℃)
Water Solubility	60 G/L (25 ºC)
Merck	14,6106
BRN	1071744
Dielectric constant	3.0（20℃）
Stability:	Stable. Combustible. Incompatible with strong oxidizing agents, acids, bases, reducing agents.
CAS DataBase Reference	553-90-2(CAS DataBase Reference)
NIST Chemistry Reference	Ethanedioic acid, dimethyl ester(553-90-2)
EPA Substance Registry System	Ethanedioic acid, dimethyl ester (553-90-2)

Safety information for Dimethyl oxalate

Signal word	Danger
Pictogram(s)	Corrosion Corrosives GHS05 Exclamation Mark Irritant GHS07
GHS Hazard Statements	H302:Acute toxicity,oral H314:Skin corrosion/irritation
Precautionary Statement Codes	P260:Do not breathe dust/fume/gas/mist/vapours/spray. P270:Do not eat, drink or smoke when using this product. 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. P303+P361+P353:IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower. P305+P351+P338:IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.