Английская Википедия:1,2-Difluorobenzene

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Шаблон:Chembox

1,2-Difluorobenzene, also known as DFB, is an aromatic compound with formula CШаблон:SubHШаблон:SubFШаблон:Sub. This colorless flammable liquid is a solvent used in the electrochemical studies of transition metal complexes. Compared to most conventional halogenated aliphatic and aromatic solvents, it possesses an exceptionally high dielectric constant (ε0 = 13.8 at 300 K). Thus, it can be a suitable solvent for cationic, and/or highly electrophilic organometallic complexes.[1]

Synthesis

Difluorobenzenes can be prepared by the Balz-Schiemann reaction, which entails conversion of diazonium tetrafluoroborate salts to their fluorides. The synthesis of 1,2-difluorobenzene starts with 2-fluoroaniline:[2]

Шаблон:Chem2
Шаблон:Chem2

The syntheses of 1,3- and 1,4-difluorobenzene proceed respectively from 1,3- and 1,4-diaminobenzene, which are doubly diazotized.[3]

Laboratory applications

Organometallic derivatives of 1,2-difluorobenzene have been well developed. It is found to be a weaker base than benzene.[4]

1,2-Difluorobenzene has been used as solvent for the electrochemical analysis of transition metal complexes. It is relatively chemically inert, weakly coordinating and has a relatively high dielectric constant. It is a weakly coordinating for metal complexes, in contrast to acetonitrile, DMSO, and DMF.[5]

It has anaesthetic properties.[6]

1,2-Difluorobenzene can be acylated to 3',4'-difluoropropiophenone.[7]

References

Шаблон:Reflist