Dication ethers-10.1 1 Part 9: Maas, G.; Feith, B. Angew. Chem., in press. Stable dipoles from a bis-acridinium ether salt and cyclic ss-diketonates

Article abstract of DOI:10.1016/S0040-4020(01)82347-4

9,9'-Oxy-bis(lO-methylacridinium) bis(trifluoromethanesulfonate) reacts with cyclic ss-diketonates by nucleophilic substitution to give deeply colored 2-acridinio-1,3-diketonates. These stable dipoles exhibit pronounced negative solvatochromism. Linear correlations between the transition energy of the solvatochromic absorption maximum and the E_T(30) as well as Z values of different solvents are found.