Showing papers by "Utsunomiya University published in 1969"

Infrared Analysis of 2-Pyrazolin-5-one Derivatives

Abstract: The ir spectra in the region 4000–250 cm−1 in the solid state have been recorded for seventy-six 1,3-di-substituted 2-pyrazolin-5-ones in which 4-positions are coupled with various diazotized anilines. Correlations between structure and frequency are made. From the results obtained, a useful application of these spectral correlations can be derived for recognizing a pyrazolinone dye in an unknown compound by means of its spectrum. The strong bands at about 1650, 1550, 1340, 1260, and 1150 cm−1, and sometimes the strong or medium bands near 1000 and 680 cm−1 constitute a good indication of the presence of a 4-arylhydrazono pyrazolinone ring.