N-ヘテロ芳香族の電子的性状(第9報) : ピラゾロン誘導体とp-キノン類との電荷移動型相互作用

抄録

New absorption bands have been observed in the visible region of the spectra of mixed solutions of p-quinones and pyrazolone dervatives : antipyrine, aminopyrine, 4-aminoantipyrine, isopropylantipyrine, and 4-bromoantipyrine. Examinations were made on the relationship between λ_max and electron affinity of p-quinones, on molar ratio, K and ΔH of the complex formations, and on the effect of polarity of solvents to the spectra. Every result obtained indicated that the new absorption bands could be ascribed to the formation of charge transfer type complexes between p-quinones and pyrazolone derivatives. Furthermore, it was informed that intensity of the new absorption bands were susceptible to the influence of substitution at the 4-position of pyrazolone derivatives ; substitution by basic groups increased K-value markedly. The authors calculated the energy levels of pyrazolone derivatives by ω-HMO method, and the values calculated were in good accord with the presumption mentioned above.