109906-91-4Relevant academic research and scientific papers
ON THE 1H-NMR SPECTRA OF HIGHLY CHARGED MULTI-TRIPHENYLMETHYLIUM IONS
Wilcox, C.F.,Hellwinkel, D.,Stahl, H.,Gaa, H.G.,Doerner, M.
, p. 5501 - 5504 (1988)
Relative to their neutral precursors, highly charged multi-tritylium ions show typical downfield 1H-NMR shifts, whereas the corresponding phenylfluorenylium ions show upfield shifts.A Hueckel based model is presented that accounts for this contrasting behavior in terms of antiaromatic ring current in the five-membered ring of the fluorenyl system with essentially null ring currents in the two six-membered rings.
