Structural study and reactivity of carbanions in solution: phenyl- and 3-pyridylacetonitriles

From the IR and 13 C NMR spectra of Li- or K-associated anionic species 1A,M formed from phenylacetonitrile in THF, it appears that monomeric tight ion pairs and THF-solvated aggregates are in equilibrium at 0.25 M concentration; the 0.025 M THF solution of 1A,Li only contains the monomer, the Li cation being likely located near the N atom of the CN moiety. In toluene-THF or hexane-THF solvent matures, solvated aggregates are predominant. In toluene-hexane, only desolvated aggregates are seen