LI+(TMPAND)NA- - THE 1ST ALKALIDE PREPARED FROM AN AZACAGE COMPLEXANT

The new lithium-selective complexant 5,12,17-trimethyl-1,5,9,12,17-pentaazabicyclo[7.5.5]nonadecane (TMPAND) was used to synthesize Li+ (TMPAND)Na-, the first alkalide prepared from an azacage complexant. This sodide was characterized by a variety of methods. Differential scanning calorimetry experiments showed a reversible, endothermic, solid-solid phase transition at an onset temperature of -75 +/- 3-degrees-C and with DELTA-H = 3.3 +/- 1 kJ/mol. Na-23 NMR spectra showed a peak at -61 ppm, characteristic of a sodium anion, and a second minor peak at -10 ppm, probably due to the interaction of Na- with trapped electrons. The quadrupole coupling constant of the complexed lithium cation was found to be 0.19 MHz at -100-degrees-C, and Li-7 NMR spectra showed a discontinuity in the line width of the Li-7 NMR peak and in the quadrupole coupling constant at the phase transition.