| Dimethoxymethane | |
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Dimethoxymethane |
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Other names
Formal Formaldehyde dimethyl ether |
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| Identifiers | |
| CAS number | 109-87-5 |
| PubChem | 8020, 10080321 (2H3)methoxy, 18424407 sulfane, 21424378 methoxymethane |
| ChemSpider | 13837190 , 8255859 (2H3)methoxy |
| EC number | 203-714-2 |
| UN number | 1234 |
| MeSH | Dimethoxymethane |
| ChEBI | CHEBI:48341 |
| ChEMBL | CHEMBL15537 |
| RTECS number | PA8750000 |
| Beilstein Reference | 1697025 |
| Gmelin Reference | 100776 |
| Jmol-3D images | Image 1 |
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| 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 |
| (verify) (what is: /?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
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| 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.