Dimethoxyethane

Dimethoxyethane, also known as glyme, monoglyme, dimethyl glycol, ethylene glycol dimethyl ether, dimethyl cellosolve, and DME, is a colorless, aprotic, and liquid ether that is used as a solvent, especially in batteries. Dimethoxyethane is miscible with water.

Production
Monoglyme is produced industrially by the reaction of dimethylether with ethylene oxide:
 * CH3OCH3 + CH2CH2O → CH3OCH2CH2OCH3

Applications as solvent and ligand
Together with a high-permittivity solvent (e.g. propylene carbonate), dimethoxyethane is used as the low-viscosity component of the solvent for electrolytes of lithium batteries. In the laboratory, DME is used as a coordinating solvent.

Dimethoxyethane is often used as a higher-boiling-point alternative to diethyl ether and tetrahydrofuran. Dimethoxyethane acts as a bidentate ligand for some metal cations. It is therefore often used in organometallic chemistry. Grignard reactions and hydride reductions are typical application. It is also suitable for palladium-catalyzed reactions including Suzuki reactions and Stille couplings. Dimethoxyethane is also a good solvent for oligo- and polysaccharides.

Sodium naphthalide dissolved in dimethoxyethane is used as a PTFE etching solution that removes fluorine atoms from the surface, which get replaced by oxygen, hydrogen, and water. This physically etches the surface as well to prepare the surface for better adhesion.