1-Butyl-3-methylimidazolium

hexafluorophosphate Hexafluorophosphate is an anion with chemical formula of . It is an octahedral species that imparts no color to its salts. is isoelectronic with sulfur hexafluoride, , and the hexafluorosilicate dianion, , and hexafluoroantimonate . In this anio ...

, also known as BMIM-PF₆, is a viscous, colourless,

hydrophobic In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, th ...

and non-water-soluble

ionic liquid An ionic liquid (IL) is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of ...

with a melting point of -8 °C. Together with 1-butyl-3-methylimidazolium tetrafluoroborate, BMIM-BF₄, it is one of the most widely studied ionic liquids. It is known to very slowly decompose in the presence of water.

Preparation

BMIM-PF₆ is commercially available. It may be obtained in two steps: BMIM-Cl is synthesized by alkylating

1-methylimidazole 1-Methylimidazole or ''N''-methylimidazole is an aromatic heterocyclic organic compound with the formula CH3C3H3N2. It is a colourless liquid that is used as a specialty solvent, a base, and as a precursor to some ionic liquids. It is a fundament ...

with 1-chlorobutane. A metathesis reaction with potassium hexafluorophosphate gives the desired compound; the tetrafluoroborate may be prepared by analogously using potassium tetrafluoroborate. : BMIM

Preparation

See also

References

Further reading