Electrochemical Formation of Oxazolines by 1,3-Oxyfluorination of Non-activated Cyclopropanes

Abstract

The C-C bond in non-activated cyclopropanes can be intramolecularly cleaved with an electrochemically generated amidyl radical forming oxazolines. In the presence of TBABF₄, this provides 1,3-oxyfluorination products. C-C bond cleavage of cyclopropane proceeds with inversion of the configuration, suggesting an intramolecular homolytic substitution (S_Hi) mechanism. The performance of TBABF₄ as an efficient fluoride source was explained by accumulation of the BF₄^- anion at the anode surface, at which a carbocation is formed by the oxidation of the C-centered radical.