Temperature-dependent hyperfine splitting constants in the electron spin resonance spectra of some furylmethanone radical anions

Abstract

The radical anions of di-2-furyl-(1) and 2-furyl-2-thienyl-methanone (2) have been prepared by electrochemical reduction in dimethylformamide, acetonitrile, and dimethyl sulphoxide. The e.s.r. spectrum of the former has been interpreted in terms of the presence of both trans,trans- and cis,trans-conformers and the activation parameters for the interconversion between these conformers have been determined. Individual conformers were not observed for the 2-furyl-2-thienylmethanone radical anion and the hyperfine splitting constants for this radical anion have been assigned by comparison with the appropriate parameters for the di-2-thienyl-, 2-phenyl-2-thienyl-, and di-2-furyl-methanone radical anions.