Dimethoxymethane

Dimethoxymethane
IUPAC name Dimethoxymethane
Other names Formal Formaldehyde dimethyl ether Methylal
Identifiers
CAS number	109-87-5 Y
PubChem	8020, 10080321 (2H3)methoxy, 18424407 sulfane, 21424378 methoxymethane
ChemSpider	13837190 Y, 8255859 (2H3)methoxy Y
EC number	203-714-2
UN number	1234
MeSH	Dimethoxymethane
ChEBI	CHEBI:48341
ChEMBL	CHEMBL15537 Y
RTECS number	PA8750000
Beilstein Reference	1697025
Gmelin Reference	100776
Jmol-3D images	Image 1
SMILES COCOC
InChI InChI=1S/C3H8O2/c1-4-3-5-2/h3H2,1-2H3 Y Key: NKDDWNXOKDWJAK-UHFFFAOYSA-N Y InChI=1/C3H8O2/c1-4-3-5-2/h3H2,1-2H3 Key: NKDDWNXOKDWJAK-UHFFFAOYAE
Properties
Molecular formula	C3H8O2
Molar mass	76.09 g mol−1
Exact mass	76.052429500 g mol-1
Appearance	Colorless liquid
Density	0.860 g cm-3 (at 20 °C)
Melting point	-104.8 °C, 168 K, -157 °F
Boiling point	42 °C, 315 K, 108 °F
Hazards
EU classification	Flammable (F) Irritant (Xi)
R-phrases	R11 R36/37/38
S-phrases	S9, S16, S33
Flash point	-18 °C
Related compounds
Related Ethers	Dimethoxyethane
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Dimethoxymethane, also called methylal, is a clear colorless flammable liquid with a low boiling point, low viscosity and an excellent dissolving power. It has a chloroform-like odor and a pungent taste. It is the dimethyl acetal of formaldehyde. Dimethoxymethane is soluble in three parts water and miscible with most common organic solvents.

It can be manufactured by oxidation of methanol or by the reaction of formaldehyde with methanol. In aqueous acid, it is hydrolyzed back to formaldehyde and methanol.

It is primarily used as a solvent and in the manufacture of perfumes, resins, adhesives, paint strippers and protective coatings.

Another useful application of dimethoxymethane is to protect alcohols with a MOM ether in organic synthesis. This can be done using phosphorus pentoxide in dry dichloromethane or chloroform. This is a preferred method to using MOM-Cl. The MOM-ether can be removed using methanol and pToluene Sulphonic Acid as an alternative to aqueous acid. Due to the anomeric effect, dimethoxymethane has a preference toward the gauche conformation around the C–O bonds, instead of the anti conformation. Since it is one of the smallest molecules exhibiting this effect, which has great interest in carbohydrate chemistry, dimethoxymethane is often used for theoretical studies of the anomeric effect.

References

• Merck Index, 11th Edition, 5936

External links

• International Chemical Safety Card 1152
• NIOSH Pocket Guide to Chemical Hazards 0396
• MSDS at Oxford University