Isolation and properties of hydrocarbon salts

Four solid hydrocarbon salts 2.1, 3.1, 4.1 and 5.1 consisting of Kuhn's anion, tris(7H-dibenzo[c,g]-fluorenylidenemethyl)methide ion (C 67 H 39 − , 1) as a carbanion moiety, and tris[1-(5-isopropyl-3,8-dimethyl-azulenyl)]cyclopropenylium (C 48 H 51 + , 2), tricyclopropylcyclopropenylium (C 12 H 15 + , 3), 1-[(2,3-diphenylcycloprop-2-enylidene)methyl]-2,3-diphenylcyclopropenylium (C 31 H 21 + , 4), or 1,3,5-tricyclopropyltropylium (C 16 H 19 + , 5) as a carbocation moiety were prepared and their properties investigated. The salt formation was proved by satisfactory elemental analyses, IR spectra (KBr disk), and UV-vis (DMSO) spectra, the spectra consisting of those of the respective cations and Kuhn's anion superimposed. Essentially complete ionization of the hydrocarbon salts 2.1 and 3.1 in DMSO was also evidenced by electric conductivity measurements