Complexes of sodium and potassium

Hu, J. Barbour, L. J., Gokel, G. W., (2001b) Solid-state evidence for pi-complexation of sodium and potassium cations by carbon-carbon triple bonds J. Am. Chem. Soc. 123, 9486-9487. 

Many jt complexes of sodium and potassium have been characterized. The Na and K atoms of these complexes are polyhapto-bonded to the ring jt systems, and frequently attached to two or more rings to give infinite chain structures. Figure 12.3.4 shows the structures of some jt complexes of sodium and potassium. 

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