J. Lin, D. Rivett, J. Wilshire
Jul 5, 1977
Citations
0
Influential Citations
20
Citations
Journal
Australian Journal of Chemistry
Abstract
Several 1,3-diphenyl- and 1,3,5-triphenyl-2-pyrazolines containing a heteroaromatic substituent (viz. imidazol-1-yl, pyrazol-1-yl and 1,2,4- triazol-1-yl) have been synthesized. When compared with their unsubstituted analogues, these compounds (a) absorbed more intensely at a longer wavelength, (b) exhibited greater fluorescence in a polar solvent (methanol) and (c) possessed similar stability to light. Large-scale irradiations of two 1,3,5-triphenyl-2-pyrazolines (viz. unsubstituted and that containing the 1,2,4-triazol-1-yl substituent) in methanolic solution revealed that, although dehydrogenation of the 2-pyrazoline ring was the major photochemical reaction, significant oxidation to the corresponding chalcone also occurred. In addition, phenol was detected among the irradiation products. Several sulphonated analogues of the abovementioned pyrazolines were prepared. When applied to wool, these compounds exhibited excellent fluorescent whitening properties.