Oligomerization of vinyl monomers. XXI. Characterization of model carbanions of living poly(2-vinylpyridine) in THF by 7Li-NMR and conductance: Evidence for the occurrence and nature of triple ion formation

The formation of triple anions is demonstrated by ⁷Li-NMR in THF solutions of 1-lithio-1-(2-pyridyl)ethane, 1-lithio-1(3-methyl-2-pyridyl)ethane, and 1-lithio-1,3-di(2-pyridyl) butane. Good agreement with conductance data was demonstrated in the case of 1 . Triple anion formation in the case of 2 was found to be about twice as high as in 1 possibly as a result of the greater charge density on the carbanion in the case of 2 .