some thiophenic and selenophenic anionic complexes, in which the Ke values for complex formation were larger than 490 M"1. It appears that a complex must have a Kc value larger than about 200 M"1 in order to be isolated.From Table III it is clear that the differences between the ki and k-X values for la" and Id" are attributable to the entropy of activation rather than to the enthalpy of activation. Here, rigorous comparison is impossible, since the data of Fendler et al. were obtained in the absence of added salt, so that ion pairing must be taken into account. The results may indicate that the transition state for the formation of la" is more solvated than that for the formation of Id", which seems reasonable, because the negative charge donated is less delocalized in la" than in Id", and consequently the former should be more solvated. According to the principle of microscopic reversibility, this should also be the case for the transition state for the decomposition of la". The result, however, is the opposite, which may be due to the ion pairing of Id" with sodium ion.

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Synthesis of 4-Hydroxyquinolines. VI. Synthesis of 3-n-Heptyl-7-methoxy-2methyl-4-quinolinol1

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