Title: Diglyme
CAS Registry Number: 111-96-6
CAS Name: 1,1¢-Oxybis[2-methoxyethane]
Additional Names: bis(2-methoxyethyl) ether; diethylene glycol dimethyl ether
Molecular Formula: C6H14O3
Molecular Weight: 134.17
Percent Composition: C 53.71%, H 10.52%, O 35.77%
Line Formula: (CH3OCH2CH2)2O
Literature References: Prepn: Cretcher, Pittenger, J. Am. Chem. Soc. 47, 163 (1925); Gallaugher, Hibbert, ibid. 58, 813 (1936).
Properties: Liquid, bp760 162°; bp200 116°; bp35 75°; bp3 20°. d2020 0.9451. mp -68°. Flash pt (open cup) 158°F (70°C). nD20 1.4097. Miscible with water, alcohol, ether, hydrocarbon solvents.
Melting point: mp -68°
Boiling point: bp760 162°; bp200 116°; bp35 75°; bp3 20°
Flash point: Flash pt (open cup) 158°F (70°C)
Index of refraction: nD20 1.4097
Density: d2020 0.9451
Use: Solvent; reaction medium for Grignard and similar syntheses.
Digoxigenin Dihexyverine Dihydralazine Dihydrazine Sulfate Dihydroactinidiolide

CAS number 111-96-6 YesY
PubChem 8150
ChemSpider 13839575 YesY
EC number 203-924-4
DrugBank DB02935
ChEBI CHEBI:46784 YesY
Jmol-3D images Image 1
Molecular formula C6H14O3
Molar mass 134.17 g mol−1
Density 0.937 g/mL
Melting point −64 °C; −83 °F; 209 K
Boiling point 162 °C; 324 °F; 435 K
Solubility in water miscible
EU classification Toxic (T)
Flammable (F)
R-phrases R60 R61 R10 R19
S-phrases S53 S45
Flash point 57 °C; 135 °F; 330 K
Related compounds
Related compounds Diethylene glycol diethyl ether, ethylene glycol dimethyl ether
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Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Diglyme, or bis(2-methoxyethyl) ether, is a solvent with a high boiling point. It is an organic compound which is the dimethyl ether of diethylene glycol. (The name "diglyme" is a portmanteau of "diglycol methyl ether.") It is a clear, colorless liquid with a slight ether-like odor. It is miscible with water, alcohols, diethyl ether, and hydrocarbon solvents.

A lithium cation being chelated by a diglyme molecule

Diglyme is mainly used as a solvent in organic reactions. It has the ability to chelate small cations, leaving anions more active. Therefore, reactions involving organometallic reagents, such as Grignard reactions or metal hydride reductions, may have significantly enhanced reaction rates.

Diglyme is also used as a solvent in hydroboration reactions with diborane.

Its stability, even at high pH values, makes it an excellent solvent for reactions with strong bases or reactions that require high temperatures.