COMPLEXATION OF DIQUAT AND PARAQUAT BY MACROCYCLIC POLYETHERS INCORPORATING TWO DIHYDROXYNAPHTHALENE RESIDUES

Article abstract of DOI:10.1016/S0040-4039(01)91375-9

NMR Spectroscopy and FAB mass spectrometry demonstrate that the 38-crown-10 (1/5DN38C10) and 35-crown-9 (1/5DN35C9) ethers incorporating two 1,5-dinaphtho units form 1:1 complexes with the Paraquat ²⁺ and Diquat ²⁺ dications in solution.In the solid state, the ²⁺ complex is stabilised by face-to-face (?/? charge transfer) interactions between the naphtho and bipyridinium rings, whereas the free 1/5DN35C9 receptor features a classid edge-to face (H^δ+/? electrostatic) interaction between its two naphtho rings.