A bouncing ball of molten sodium metal during the reaction with triphenylphosphine in diglyme.

Diglyme is a high boiling point (162 °C (324 °F; 435 K)) etheral solvent what is often used in organic synthesis, since it has the ability to chelate small cations, leaving anions more active.

When adding sodium metal (shiny metal ball floating over there) to a solution of triphenylphopshine in diglyme, phenyl sodium and sodium diphenylphosphide will form (that orange colored thing at the surface of the sodium at the fourth gif). The reaction will only happen if the solvent does not contain any water, but when it starts, the whole solution will turn blood red in a few minutes (last gif).

Sodium has a low melting point (97.8 °C ​(​208 °F, 371 K)), so it’s easily melted in the hot diglyme solutions, since it does not react with it. Any protic solvent (any solvent that contains labile H+) would react with sodium, so the same trick could not be done e.g.: with water.

9:30 pm • 15 March 2016 • 184 notes • View comments