1,2-Difluorobenzene, also known as DFB, is an

aromatic In chemistry, aromaticity is a chemical property of cyclic ( ring-shaped), ''typically'' planar (flat) molecular structures with pi bonds in resonance (those containing delocalized electrons) that gives increased stability compared to satur ...

compound with formula CHF. This colorless liquid 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 ...

used in the

electrochemical Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential difference, as a measurable and quantitative phenomenon, and identifiable chemical change, with the potential difference as an outco ...

studies of transition

metal complexes A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...

Synthesis

1,2-Difluorobenzene is prepared by a simple substitution reaction of

fluorine Fluorine is a chemical element with the symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as a highly toxic, pale yellow diatomic gas. As the most electronegative reactive element, it is extremely reacti ...

with

fluorobenzene Fluorobenzene is the chemical compound with the formula C6H5F, often abbreviated PhF. A colorless liquid, it is a precursor to many fluorophenyl compounds. Preparation PhF was first reported in 1886 by O. Wallach at the University of Bonn, who ...

. :CHF + F → CHF + HF The 1,4-

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

and small amounts of the 1,3-

are also produced in the reaction as the fluorine group on the aromatic ring of

is ortho- and para- directing.

Applications

1,2-Difluorobenzene has been used as solvent for the

analysis of transition metal complexes. It is relatively chemically inert, weakly coordinating, and has a dielectric constant high enough to dissolve many electrolytes and metal complex salts. It is used as a weakly coordinating solvent for metal complexes, alternative to the relatively more strongly coordinating solvents

acetonitrile Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile (hydrogen cyanide is a simpler nitrile, but the cyanide anion is not clas ...

DMSO Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula ( CH3)2. This colorless liquid is the sulfoxide most widely used commercially. It is an important polar aprotic solvent that dissolves both polar and nonpolar compounds an ...

, and DMF. It has a role as an anaesthetic. 1,2-Difluorobenzene can be acylated to 3',4'-difluoropropiophenone, which has interesting application in the synthesis of halogenated cathinone/PPA congeners.

Hazards

DFB is a highly flammable liquid and vapour. Hazardous decomposition products formed under fire conditions include carbon oxides, and

hydrogen fluoride Hydrogen fluoride (fluorane) is an inorganic compound with the chemical formula . This colorless gas or liquid is the principal industrial source of fluorine, often as an aqueous solution called hydrofluoric acid. It is an important feedstock i ...

. Handle with thick fluorinated rubber gloves.

References

{{DEFAULTSORT:Difluorobenzene, 1, 2- Fluoroarenes Halogenated solvents Aromatic solvents