2,2´-Biquinoline誘導体に関する研究 (第5報)

Abstract

Examinations were made on chelates of 47 kinds of 2, 2′-biquinoline derivatives, including three known compounds, and copper (I) on the effect of changes in the kind and position of the substituent and changes in spectrophotometric constants (ε, λmax). Examinations were made with 2, 2′-biquinolines with substituents in 4- and 4′-positions, presence of substituents in 6, 6′-, 7, 7′-, and 8, 8′-positions in the 4, 4′-dimethyl compound, presence of methyl groups in 6, 6′-, 7, 7′- and 8, 8′-positions in 4, 4′-dimethyl compound, and presence of substituents in 6, 6′-, 7, 7′-, and 8, 8′-positions in 4, 4′-diphenyl compound, as well as with polysubstituted compounds. The maximum sensitivity was found in 4, 4′-diphenyl-6, 6′-dimethyl-2, 2′-biquinoline (ε 11030) and (2, 2′-biquinoline)-4-carboxylic acid and -4, 4′-dicarboxylic acid were found to undergo this reaction in aqueous solution. Further introduction of a substituent in 6, 6′- or 7, 7′-position in 4, 4′-substituted compounds indicated that the absorbency is greater in 6, 6′-substituted compounds, being hyperchromic, while maximum absorption is batho-chromic in 7, 7′-substituted compounds. 8, 8′-Substituted compounds and N-oxides lost the ability to undergo coloration reaction with copper (I) due to steric hindrance.