Diglyme, or bis(2-methoxyethyl) ether, is a

solvent A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for ...

with a high

boiling point The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. The boiling point of a liquid varies depending upon the surrounding env ...

. It is an

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. Th ...

which is the dimethyl

ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again ...

of diethylene glycol. (The name ''diglyme'' is a

portmanteau A portmanteau word, or portmanteau (, ) is a blend of wordsethylene oxide over an acid catalyst.

Solvent

Because of its resistance to strong bases, diglyme is favored as a solvent for reactions of alkali metal reagents even at high temperatures. Rate enhancements in reactions involving

organometallic Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and s ...

reagents, such as Grignard reactions or metal hydride reductions, have been observed when using diglyme as a solvent. Diglyme is also used as a solvent in hydroboration reactions with diborane. It serves as a chelate for alkali metal

cation An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conven ...

s, leaving

anion An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conve ...

s more

active Active may refer to: Music * ''Active'' (album), a 1992 album by Casiopea * Active Records, a record label Ships * ''Active'' (ship), several commercial ships by that name * HMS ''Active'', the name of various ships of the British Royal ...

Safety

The European Chemicals Agency lists diglyme as a Substances of Very High Concern (SVHC) as a Reproductive Toxin. At higher temperatures and in the presence of active metals diglyme is known to decompose, which can produce large amounts of gas and heat. This decomposition led to the T2 Laboratories reactor explosion in 2007.{{Cite journal, last1=Willey, first1=Ronald J., last2=Fogler, first2=H. Scott, last3=Cutlip, first3=Michael B., date=March 2011, title=The integration of process safety into a chemical reaction engineering course: Kinetic modeling of the T2 incident, url=https://onlinelibrary.wiley.com/doi/10.1002/prs.10431, journal=Process Safety Progress, language=en, volume=30, issue=1, pages=39–44, doi=10.1002/prs.10431, hdl=2027.42/83180, s2cid=109207593, hdl-access=free

References

Glycol ethers Chelating agents