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1.Electrolytic fluorination of organic compounds in the presence of the electrolyte containing the complexes of anhydrous hydrogen fluoride and trialkylamines.

For  electrolytic fluorination method  the new nonviscous at room temperature electrolytes of R₄NF* nHF or R₄NF *3HF was used. The electric conductivity of such solutions reported in Table 1.

Table1. The electric conductivity of the solutions in MeCN containing 1 mol/dm³R₄NF*nHF è Et₃N *3HF(1b)

Using of the complexes of hydrogen fluoride with the bases as electrolytes brings to selective introduction of one fluorine atom (17-25). Platinum is still a frequently usable electrode but using the anodes made of the other material (for example graphite, rhenium) gives good results. Acetonitrile is the best accessible solvent to perform the process of the electrolytic fluorination, however, the possibilities to use the other solvents, for instance dimethoxyethane, were shown. A high selectivity and a high yield make this fluorination method not only important to produce fluoroorganic compounds but largely perspective to produce the fluorine-containing heterocyclic and the natural substances as well. In spite of a curtain progress on obtaining desired low-fluorinated compounds by this way for now, the method is economically unsuitable due to extraction complexity of the reaction products and low selectivity.

The process of organic compound fluorination including fluorine addition to a multiple bond and hydrogen substitution for the fluorine in a hydrocarbon chain is a reduction – oxidation process due to fluorine possesses the greatest possible electron affinity (4.15 eV) and the highest standard potential of reduction-oxidation reaction (2.87 V).

Compounds with multiple bond undergo the anodic fluorination at a platinum anode in Et₃N*3HF/MeCN system. So, the anodic fluorination trans- and cis- 1,2-diphenylethylene brings to the formation of product mixture (2b).

The anodic fluorination of ,-unsaturated carbonyl compounds having alkylthioxy group  attached to a multiple bond 1(27) and vinylthioethers 2 (28) in Et₃N*3HF electrolyte in the acetonitrile medium results in the formation of -fluoro--thio-,-unsaturated carbonyl compounds and -fluorodialcylsulfides. 

Vicinal difluoroderivatives 3 are originally formed, then the substances are dehydrofluorinated by E1cB mechanism, giving the monoflorination product 4 with the high selectivity. The Data of the anodic fluorination of vinylethers reported in Table 2.

Table 2. Anodic fluorination of vinylethers (28).

It is interesting that trans-2 (phenylthio) styrene (mixture E/Z=90/10) gives ,,-trifluorosubstituted sulfide 7 (28).

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