Radical anions of trimethylsilyl-substituted NN-dimethylanilines

Abstract

The introduction of a trimethylsilyl ring substituent sufficiently enhances the electron affinity of NN-dimethylanilines to permit metal reduction to radical anions in mixed ether solvents. The e.s.r. spectra of the radical anions of o-, m-, and p-trimethylsilyl-NN-dimethylaniline, the first examples of NN-dialkylaniline radical anions which do not have strongly electron-withdrawing ring substituents, are reported. They indicate that the electron-withdrawing effect of the trimethylsilyl group in the ground states of radical anions is equal to or slightly greater than the strong electron-donating effect of the dimethylamino-group.