Beyond the structures of these cyanomethyl complexes, the significant scientific result demonstrated by these reactions is that coordination to these Pd centers makes the C-H bonds of acetonitrile molecules considerably more acidic than anticipated, as the bases used in these studies are much milder than those typically used to form metal-cyanomethyl complexes. This enhanced acidity is relevant to potential catalytic applications using cyanoalkyl nucleophiles. The pKa of CH3CN is defined by its autoionization constant, equation (5), where H + (sol) is the solvated proton. A pKa value of at least 33.3 (Kauto ≤ 1x10 - 33.3 ) was painstakingly estimated by Chantooni and Kolthoff for equation (5) through conductivity measurements, but although this value is widely used, it was identified at the time as being a lower limit on the actual value. The measured value of 33.3 is likely to be too low due to the presence of impurities in the conductivity experiments. Schwesinger has since suggested that the true value may be as high as 44. Morris proposed that a value of approximately 39 was likely to be correct, because strongly basic phosphazenes with pKa BH+ values up to approximately 38 can be studied in this solvent (where pKa BH+ refers to the pKa of the conjugate acid of the base), but stronger bases decompose the solvent.