The ultra-violet absorption spectra of dehydrothio-p-toluidin and some of its derivatives

✍ Scribed by Edisbury, J. R. ;Hunter, R. F. ;Scott, A. D.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1948
• Weight: 219 KB
• Volume: 67
• Category: Article
• ISSN: 0368-4075
• DOI: 10.1002/jctb.5000671009

✦ Synopsis

Abstract

The ultra‐violet absorption spectrum of a very pure specimen of dehydrothio‐p‐toluidine (4′‐amino‐2‐phcnyl‐6‐methyl benzthiazole), which was measured by photographic spectrophotometric technique and redetermined with a Beckman photoelectric spectrophotometer, shows a strong absorption band at 345 mμ. and a rudimentary band at 260 mμ. Acetylation and benzal condensation of the 4′‐amino group result in a shift of maximum to the region of shorter and longer wave length respectively, and substitution of a p‐NMc, group in the 4′‐benzylidcncaminc substituent results in a considerable increase in intensity accompanied by the appearance of a subsidiary maximum close to the rudimentary band in dehydrottuo‐p‐toluidine. Replacement of the 4′‐amino group by hydroxyl is accompanied by a shift of absorption to shorter wave length with loss of intensity, both of which arc further affected in the same direction by acetylation.