ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Polycondensation of aromatic isothiocyanates

P. Kristián, Š. Kováč, K. Antoš, and A. Hulka

Slovak Technical University, Bratislava

Abstract: The polycondensation of aromatic isothiocyanates and their infrared absorption spectra were described. By adding CSCl₂ to the amine in acetone-water or CHCl₃-water systems 2-anthracenylisothiocyanate, m. 199-200°, 2-anthraquinoliso- thiocyanate, m. 208°, 3-pyrenylisothiocyanate, m. 125-6°, and 6-chrysenylisothiocyanate m. 175-6° were prepd. Prepns. of 3-pyrenyl- and 6-chrysenylisothiocyanate were already described, but not by the CSCl₂ method. These isothiocyanates were compared with 2-naphthylisothiocyanate in infrared absorption spectra, 3200-670 cm^-1 All isothiocyanates give strong broad absorption bands around 2100 cm^-1, corresponding to asymmetric valence vibrations of the NCS group. The absorption bands in this region are split by Fermi resonance into several max., from which the max. in the region 2200-2150 cm^-1 are displaced to higher wave nos. with increasing no. of condensed aromatic rings. A strong band or a group NCS (νasym. NCS = 2030 cm^-1) at 2-anthraquinolisothiocyanate is moved considerably to lower wave nos. as compared with other isothiocyanates (Vasym NCS = 2100 cm^-1.). At ν = 940 cm^-1 the prepd. isothio- cyanates show relatively strong bands which should correspond to symmetric valence vibrations of the NCS group. The position of this absorption wave in all isothiocyanates prepd. is displaced to higher wave nos. as compared with phenylisothiocyanate (νsym. NCS = 927 cm^-1).

Full paper in Portable Document Format: 167a542.pdf (in Slovak)

Chemical Papers 16 (7) 542–552 (1962)